%, ^. '%. 5>^. \% IMAGE EVALUATION TEST TARGET {MT-3) 4p 4y /J^4i. 1.0 If I.I 11.25 -121 50 ""^ 2.5 li IIIIM III 1.8 1.4 1.6 V] y] / -(^ Photographic Sciences Corporation 73 WEST MAIN STREET WEBSTER, N.Y. 14580 (716) 872-4503 f/j CIHM/iCMH Microfiche Series. CIKM/ICIVIH Collection de microfiches. Canadian Institute for Historical Microreproductions / Institut Canadian de microreproductions historiques Technical and Bibliographic Notes/Notes techniques et bibliographiques The Institute has attempted to obtain the best origin&l copy available for filming. Features of this copy which may be bibliographically unique, which may alter any of the images in the reproduction, or which may significantly change the usual method of filming, are checked below. D Coloured covers/ Couverture de couleur I j Covers damaged/ Couverture endommag6e Covers restored and/or laminated/ Couverture restaurie et/ou peiliculie Cover title missing/ Le titre de couverture manque Coloured maps/ Cartes g^ographiques en couleur Coloured ink (i.e. other than blue or black)/ Encre de couleur (i.e. autre que bieue ou noire) Coloured plates and/or illustrations/ Planches et/uu illustrations en couleur Bound with other material/ Reli6 avec d'autres documents □ Tight binding may cause shadows or distortion along interior margin/ La re liure serr6e peut causer de I'ombre ou de la distorsion le long de la marge intdrieure □ Blank leaves added during restoration may appear within the text. Whenever possible, these have been omitted from filming/ II se peut que certaines pages blanches ajouties lors d'une restauration apparaissent dans le texte, mais, lorsque cela 6tait possible, ces pages n'ont pas 6x6 film^es. L'Institut a microfilm^ le meilleur exemplaire qu'il lui a it* possible de se procurer. Les details de cet exemplaire qui sont peut-dtre uniques du point de vue bibliographique, qui peuvent modifier une image reproduite, ou qui peuvent exiger une modification dans la mithode normale de filmage sont indiquis ci-dessous. D D D D D □ D D Coloured pages/ Pages de couleur Pages damaged/ Pages endommagdes Pages restored and/or laminated/ Pages restaur^es et/ou peliiculdes Pages discoloured, stained or foxed/ Pages d^color^es, tacheties ou piqu6es Pages detached/ Pages d^tach^es Showthrough/ Transparence Quality of print varies/ Quality indgale de I'impression Includes supplementary material/ Comprend du materiel suppldmentaire Only edition available/ Seule Edition disponible Pages wholly or partially obscured by errata slips, tissues, etc., have been refilmed to ensure the best possible image/ Les pages totalement ou partieilement obscurcies par un feuillet d'errata, une pelure, etc., ont 4td filmies 6 nouveau de facon t^ obtenir la meilleure image possible. Additional comments:/ Commentaires supplimentaires: Irregular pagination : [i] - vi. [5] - 135 p. This item is filmed at the reduction ratio checked below/ Ce document est film* au taux de reduction indiqui ci-dessous. ■[OX 14X 18X 22X 26X 30X 7 12X 16X 20X 24X 28X 3 32X The copy filmed h«r« has be«n reproduced thanks to the generosity of: D. B. Weldon Library University of Western Ontario (Regional History Rooti ) The images appearing here are the best quality possible considering the condition and legibility of the original copy and i»i keeping with the filming contract specifications. Original copies In printed paper covers are filmed beginning with the front cover and ending on the last page with a printed or illustrated impres- sion, or the back cover when appropriate. All other original copies are filmed beginning on the first page with a printed or illustrated impres- sion, and ending on the !ast page with a printed or illustrated impression. The last recorded frame on each microfiche shall contain the symbol -^(meaning "CON- TINUED"), or the symbol V (meaning "END"), whichever applies. l\Aaps. plates, charts, etc., imay be filmed at differei:t reduction ratios. Those too large to be entirely included in one exposure are filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames as required. The following diagrams illustrate the method: L'exemplaire filmA fut reproduit grdce d la g^nArositi de: D. B. Weldon Library University of Western Ontario (Regional History Room) Lee images suivantes ont «t« reproduites avec le plus grand soin. compte tenu de la condition at de la nettet* de l'exemplaire fllm«. et en conformity avec les conditions du contrat de fiimage. Les exemplaires origlnaux dont la couverture en papier est imprlmte sont filmte en commenpant par le premier plat et en terminant soit par la darniire page qui comporte une empreinte d'Impression ou d'illustratlon, soit par le second plat, salon le cas. Tous lee autres exemplaires origlnaux sont film6s en commenpant par la premiere page qui comporte une empreinte d'Impression ou d'illustratlon et en terminant par la derniire page qui comporte une telle empreinte. Un des symboles sulvants apparaftra sur la dernlAre image de cheque microfiche, se!on le caa: le symbols — ^ signifie "A SUIVRE ", le symbols V signifie "FIN". Les cartes, planches, tableaux, etc., peuvent dtre filmte A dee taux de reduction diffirents. Lorsque le document est trop grand pour dtre reproduit en un seul cliche, il est film« d partir de Tangle supirieur gauche, de gauche d droite, et de haut en baa. en prenant le nombre d'Images nteessaire. Les diagrammes sulvants illustrent la m^thode. 1 2 3 1 2 3 4 5 6 'X4':f'. ^:> :r),Cjp.M^;» -4^ J -3 '4 V ' - .' M)(m clTO^l 8'T^3rr:TT3 p^iMM an ') n vt,l:<^;-:;;/^s; ^.v,' / ■i i.jf „yiiHiiSij(p iSir^IiJl ^OTMOEoY PREFACE. The sole object of the following compilation is to present to the Student the principal facts of Chemistry in so con- densed a form as to obviate the necessity in a very gieat measure of his writinj? notes on the subject. It is simply intended to serve him as an " aide memoire " in Inorganic Chemistry, and not at all to «uperaede the ordinal^ test- books on the science. A list of standard' works ODtheyaiJttus departments of chemical science, isgiv6n at the end of the volume ; end to some of these, the student must of course apply himself for any detailed information upon methods of procedure, theoretical discuasions, and notices of the innu- merable less important chemical compounds. The older nomenclature is observed throughout, as being that generally met with, and least likely to present difficulties to the student. Toronto, August, 1862. .^:-A n: •B T H S T H ;.7«i3ai>fn;,.>., »iT" -i'ji ERRATA. Page 9, Art. 22, for "bases" read " binaries." ' '^;'^ Page 16, Art. 48, for "acids" read "^cwc^.^.rf.nr'^^T S-rs'SaJj^Sj:^ Page 00, omit the heading " ohbihcal phtsios." auxqinioilh. Page 39, Art. 132, first Une for "two vol. of O and one volume of H " read " two vol. of H and one volume of O." " ' ■ ■■'"-•-■■...........,;. „ , -lutiur^S ■ ■> i. .. . •, , „ . .-ji.'Kif.ji^ mi}h3i:£ •:ii>CJJC': CONTENTS. PAOS. Deflnitions and Nomenclature 6 Table of Elements 7 Laws of Chemical Combination 12 Table of Combining Volumes 16 Chemical Notation I7 Chemical Affinity jg Atomic Theory 24 Crystallization , 26 Isomorphism and Isomerism 29 Allotropism , , 90 Oxygen SO Hydrogen , , 93 Water., *]].. 99 Nitrogen ^ Carbon ^ Chlorine. 53 Iodine, Bromine, and Fluorine 67 Sulphur 59 Phosphorus 03 Selenium and Borax „ gg The Metals (generally) ...*. qo Salt-Radical Theory ] 75 Potassium , . , , , 79 Sodium gj Lithium and Ammonium v 94 Calcium 95 Magnesium ^ 97 Barium ,,.., 99 Strontium ,, , 99 Aluminum qq Zinc, Nickel, and Cobalt ."...!!!.' 92 Cadmium and Copper ; .^ 09 Manganese abd Iron ,...] 95 Lead.... » " en m^ Z • ux» ......tit «•»•..••»..•.»•»».. <......»,,.r..,,,. 90 vi CONTENTS. Cbromiam 100 BianiuMi 102 Antimony 102 Ai'sciiic •. 104 Silver 107 G old 108 Flaf inum , 109 Morou ry 110 BeagCDf8, p' oparation of 115 Bcactions of the lbn>going elcmenlii and their compounds 119 Appendix 1, Gcrhardt's notation 1G2 Appendix '2, List of Apparatus and Bcagcnts 138 Appendix B, Liat of woi ks oa Ciiopiiktry. 19^ CHEMISTRY. LECTURE I. DEFINITIONS AND NOMENCLATURE. 1. Chemistry is the science which investigates the nature, properties, and mutual relations of the various elements that enter into the composition of the diflTerent bodies with which we are acquainted ; or Chemistry may be defined to be the science which teaches us the mode of resolving ^ompound body into its elementary constituents, and of confMning two or more elementary bodies into a compound. 2. Chemistry is divided into two branches : 1st. Inorganic Chemistry. 2nd. Organic C hemic; ;. 3. Inorganic Chemistry is that department of chemistry which treats of the simple elements that enter into the composition of all known bodies, and of the chemical compounds formed by their union. 4. Organic Chemistry treats of the peculiar compounds into which the living plant or animal converts the ultimate elements of its food, and of the substances thai enter mto the structure of :^ oriranized hAincra n ^ ' ^^ 6 NOMENCLATURE. 6. Ohemical Nomenclature was, before the discovery of oxygen very loose and complicated, substances receiving the most trivial names. Thus Sulphate of Magnesia was called Epsom Salts, from tho Springs of Bpsom ; Sulphate of Soda was called Glauber's Salts, from its discoverer Ac. e. The Nomenclature at present in use was constructed by I^avoisier and his associates, towards the end of last century, NOMENCLATUBE. 7. All natural bodies are divided into two classes : 1st. Elementary or Simple Bodies. 2nd. Compound Bodies. 8. An element or elementary body is a body which in the present state of the science, is incapable of being resolved, by chemical analysis or other means, into two or more dissimilar bodies. 9. A compound body is a body resulting from the union of two or more elements. 10. The Elements at present recognized number 65, of which 13 are called Metalloids, and the remaining 52, Metals. NoTB.— The nunjb^r is somewhat uncertain, some Chemists admitting only 62. ' JIK 11. The 13 Metalloids, with their symbols, are as follows : Element. IL Oxygen, , Hydrogen, . , Nitrogen,..., Carbon, Sulphur, Chlorine, i I Phosphorus, [p H N s CI to 11 8 1 14 6 16 35.6 32 Element. Silicon, .... Iodine, Boron, Bromine, . Fluorine, . Selenium,. o ,0 cc Si I B Br F Se to 21.3 127 11 80 Id 40 M ■ '■ ■ » I = i 12. The 62 Me^ls, with thefr symbols and combining num- ti bers, are as follows : ' . _ v .,' '-f^ NOMENCLATURE. Element. am S I CO Aluminum a1 Antimony (Stibium) Sb Arsenic As Aridium A.r Barium Ba Bismuth Bi Cadmium cd Calcium Ca Cerium Co Chromium Or Cobalt Co Copper (Cuprum) Ou Didymium D Donarium Do Erbium q Glucinum Iqi A.U [r Pe [1 Ln Pb Li c5^ 13.7 129 75 Element. Gold (Aurum) Iridium Iron (Ferrum) Ilmenium Lanthanum Lead (Plumbum) Lithium .\ Magnesium Manganese Mercury (Hydrargyrum). 69 71 56 20 40 28 30 32 60 80 26.5 98.5 09 28 60 48 104 0.4 12.5 iVIa J27. 5 Hg ilOO Molybdenum Nickel "." Niobium Norium Osmium Palladium Pelopium Platinum Potassium (Kalium) . ... Rhodium Ruthenium Silver (Argentum) Sodium (Natrium) Strontium Tantalum or Columbium Tellurium Terbium Thorium Tin (Stannum) Titanium Tungsten (Wolfram). Uranium Vanadiua|l||^ Yttrium?^ Zinc Zirconiiun i Mo Ni s .a No Os Pd Pt K R Ru Ag Na Sr- Ta Te Tb Th Sn Ti W U V If Zn Zr 48 29.5 99. J 98.5 39 52 62 108 23 44 93 66 59. b 69 24 95 CO 68.6 ■)2 32.5 32.5 13. Those elements long known retain their common names. Examples.— Gold, Silver, Tin, Iron, Lead, &c. 14. Those elements more recently discovered take a name indicative of some prominent property. Examples.— Chlorine from chloros, " green," in allusion to its color. Iodine from ion, a " violet," and eidos, " resem- blance," from its viplet-colored fumes. Bromine from bromos, "fcetor,* referring to its intensely Uisagreeable odour. 8 NOHINOLATUBB. ■!#.. Ohromiam from chroma^ a " color," in allusion to the brilliant colors of its compounds. Glttcinum from glukus, "sweet/* its compounds being distinguished by a sweetish taste. Oxygen from oxtM, "acid," and gennaoj "I generate or produce." Hydrogen from hudor, " water," and gennao^ &c. 15. Compound Bodies may be divided into — 1st. Acids. 2nd. Sases. 3rd. Salts. 16. Acids have a sour taste, redden yegetable blues, and neutralize alkalies. 17. Bases have an acrid taste, restore to blue the color reddened by an acid, and neutralize acids. 18. Salts are bodies arising from the union of acids with bases. 19. Salts are divided into three classes : 1st. Neutral Salts, or those in which neither the acid nor the base predominates. 2nd. Acid Salts or Super Salts, or those in which the acid is i^zcess. 3rd. Basic Sms or Sub-Salts, or those in which the base is in excess. 20. Acids prefix per, hyper, and hypo, and affix -ic and -ous. "n^ ^1. Of the firat element named in the compound,— except in case of the compounds of oxygen, when they always refer to the Q p^r or hyper means more than -ic, and -ic more than ous, while hypo implies leas than 4c or -ous respectively. Thus the eompovrnds of oxygen and chlorine are named as follows : — Perchloric acid or Hyperchloric acid = CIOt, i. e. a com- pound of seven equivalents of to one of CI. • Chloric acid = ClO^, i, e. a compound of five equiralents of O to one of CI. • '"Hypochloric acid = C/O4, i.e. a compound of /our equiva- lents of to one of CI. ♦ NOMENOLATUBE. lia * Chlorous acid= C/O3, i. e. a componnd of three equivalents of to one of CI. Hypochlorous acid = CIO, !. e. a compound of one equiva ent of O to one of CI. 22. Bases affix -ide. It was formerly the custom to limit the affix -ide to bases of which the first element named was oxygen or a metalloid ending in -ine, as chlorine, bromine, iodine, ic, and to apply the affix -uret in all other cases. This is, however, now falling into disuse, and the affix -ide is used for all bases ex- cept certain oxides in which the affix -a stands for the word oxide. Examples.— Potassa = oxide of if ; Soda = oxide of Na; Silica = oxide of Si ; Alumina = oxide of ^/ ; Magnesia = oxide of Mg, &c. 23. Salts formed from acids in -ic enc a -ate. ExAMPLJia.— Sulphuric acid and soda unite to form tulphate of soda. iVtYnc acid and potash unite to form nitrate of pot- ash. Metic acid and iime unite to form acetate of lime. Chloric acid and potash unite to form chlorate of potash, &C. 24. Salts formed from acids in -ous end In -ite. ExAMPLEa.— Sulphurous acid and soda unite to form sulphite of soda. Chlorous acid and potash unite to form chlorite of potash. Phosphorous acid and potash unite to form phos- phite of potash. 25. Salts formed from acids inpe?', hyper, or hypo, always retain the per, hyper, or hypo. ^xkuPLES. —Hypophosphorous acid and potash unite to form hypophosphite of potash. Hypochlorous acid and potash unite to form hypo- chlorite of potash. Hyposulphurous a.cid &nd soda unite to form hypo- ■X sulphite of soda. 10 NOMENCLATURE. Perchloric acid and potash unite to form perchlo- rate of potash. Permanganic acid and potash unite to form per- manganate of potash. 26. When a body is capable of forming two or more com- pounds with oxygen or another body, these compounds are dis- tinguished from each other by the prefixes Proto, Bi or Deuto^ Ter or Trito, and Sesqui, which always refer to oxygen if it be present ; if not, to the first element named. Proto = 1. Examples — Protoxide of Iron = JPeO = one equivalent of O to one of Fe. Protosulphide of Mercury = HgS = one equivalent of S to one of Hg. Protochloride of Copper = CuCl = one equivalent of CI to one of Cu. Dbuto or Bi = 2. Examples.— Binoxide of Manganese rrifnOa = two equiva- lents of O to one of Mn. Bicarbonate of Soda = NaO^lCO^ = two equivalents of Carbonic Acid to one of Soda. Bichloride of Mercury = HgCl^ = two equivalents of CI to one of Hg. Deutoxide of Hydrogen = HOc^ = two equivalents of O to one of H. Teito or Ter = 3. Examples.— Tersulphide of Potassium = KS^ = three equiva- lents of 8 to one of K. Teroxide of Antimony = SbOs = three equivalents of to one of Sb. Sesqui = 3:2. Examples.— Sesquioxide of Manganese = Mn^O^ = three equivalents of O to two of Mn, Sesquisulphide of Chromium = Crg/S^g = three equivalents of S to two of Cr. Sesquichloride of Aluminum = M^CL =■ three equivalents of CI and two of Jll. NOMENCLATURE. n 27. Binary Oompounfl;.' ; s such as result from the union of two simple elements. Examples.— Bisulphide of Iron, FeS^ ; Water, HO ; Sulphuric Acid, SO3; Oxide of Phosphorous, PgO; Chloride of Sodium, NaCl, &c, 28. Ternary Compounds are such as result from the union of two binary compounds. Examples. — Sulphate of Soda, NaO, SO^ ; Carbonate of Lime, CaO,COi ; and generally all bodies formed by the union of an acid with a base, or, in other words, all salts. 29. Quaternary Compounds result from the union of two ternary compounds, or, in other words, of two salts. Example.— Alum, which is KO^SO^-^jll^O^, 3503+24^0. 30. Radicals are those bodies which are capable of chemically uniting with one another, and are divided into— 1st. Simple Radicals. 2nd. Compound Radicals. 31. The Simple Radicals are the simple elementary bodies, as Oxygen, Hydrogen, Carbon, Sulphur, &c. 32. A Compound Radical is a chemical compound which, although containing two or more elements, enters into combi- nation with elementary bodies, as though it were itself elemen- tary ; or a compound radical may be defined to be a compound substance which can be made to take the place of a simple element in certain chemical combinations. As examples of compound radicals, the following may be given :— Cyanogen, CgN Carbonic Oxide, CO. Ethyle, C4H5 Benzoyl, C14H5O2 Ammonium, NH4 Mellone, C6N4 Acetyle, C4H3 Methyle, C2H3 Salicyle,Ci4H5 04 Kakodyle, C4H6AS. 33. When a compound body is decomposed by galvanic elec- tricity, those elements that go to the positive pole are termed dectrc-negaiive, and those that proceed to the negative pole are called electro'poaitive bodies. 12 LAWS OF LECTURE it. Laws op Combination.— I. Law af Fixer ProportioM; 11. Law of Multiple Proportions ; III. LaMd of jCquivalent Proportions; IV. Law of Combining Number of Compounds—Symbols^ Combining Numbers^ Chemical Noiation-^Relation between the Atomic Weights^ Specific Gravities, and Combining Volumes of those Elements that exist in a Gaseous State. LAWS OF CHEMICAL COMBINATION. 84. First Law.-^MI chemical compounds are definite in their nature, the ratio of the elements being constant. 35. This law is the result of chemical analysis, and is proved by synthesis. EXAMPLB.—9 grains of water = one grain of H and eight grains of O ; also 8 grains of O and 1 grain of li produce 9 grains of water. 36. The converse of this law is far from being true : the same elements combined in the same proportions do not of necessity generate the same substance. BxAMPLK. — Oil of roses and illuminating gas are identical in chemical composition ; as also are sphrits of turpentine, oil of lemons, oil of juniper, oil of black pepper, and oil of bergamot. 37. Second Law.— W^en a body is capable of combining with anouer in several proportions, these proportions bear a simple numerical relation to each other. Thus, if A and B represent the two bodies that unite, their compounds will be as follows : FIRST SERIES. •^+B ist compound J5 = 1 ' A+BB 2nd « B=z2 A-\-BBB 3rd " JB = 3 J-i-BBBB 4th " J5 = 4 «a^X9J3J3XljD OLU " H— fi . CHEMICAL COMBINATION. ExAMPLK.— In the compounds of N and O we have— 1st. NO or 14 grs. o N unite with 8 grs. of 13 2nd. NO2 or 14 (( N (( 16 (( 3rd. NO3 or 14 (( N « 24 i( 4th. NO^ or 14 « N It 32 11 5th. JVO5 or 14 « N (( 40 u T SECOND SBBIKS. .i-^BBB 1st compound J :B ::1 : Jl-\-BBBBB 2nd " Jl:B::l: Ji+BBBBBBB 3rd " JiiB-.-.l ExAMPLH. — In the compounds of Arsenic with Oxygen we have— 1st jSsO^ or 75 grs. ofJls unite with 24 of 0. 2ndwtf«05or75 " of As « 40 of 0. Sometimes one or more members of a series are wantiig, as in compounds of CI and 0, which are CIO, CZO3 , CIO 4, , CZO5 , and CZO7, in which ClO^ and ClO^ are wanting or do not exist. 88. Thibd Law. — If a body, A^ unite with other bodies, B, C, D, the qtiantities of B, C, D which unite with A will represent in numbers the proportions in which they unite among theihselves in case such union takes place. . Illustration. — 8 grs. of O unite with 1 gr. of H; or with 16 grs. of /S; or with 14 grs. ofN] or with 35'5 grs. of CI. Then 1, 16, 14, and 35'6 are the chemical equivalents or combining numbers of JET, S, N, and CI ; that is, if any of these bodies unite to form a compound, the union always takes place in quantities proportional to these numbers. ExAMPLB.— If and CI unite to form HCl or hydrochloric acid, in which 1 gr. of H+ 35-5 grs. of CI = 36-5 grs. of HCl. The number 35*5 is called the chemical equivalent of C/, because that many grains of CI go as far as 8 grains of O in saturating any amount of H, &c. 30. Chemical Equivalents are likewise called Combining Numbers and Atomic Weights. 40. The following are the Symbols and Combining Numbers 14 LAWS OF Of iho principal elements.* It is necessary to remember that iTstands not only for Hydrogen but for one equivalent of it • 8 represents one equivalent of Sulphur ; K one equivalent of Elements. Metalloids. Hydrogen.. Oxygen Nitrogen.... Carbon Clorine Sulphur Phosphorus., Boron Bromine , Fluorine Iodine Sili^n.i'. Symbols. H O N C CI S p B Br F I Si Comb. No. I Selenium Se 1 8 14 6 35.5 16 32 11 80 19 127 21.3 4u Elements. Metals, Potassium.,.. Sodium Calcium Aluminum,... Magnesium. .. Manganese Iron Lead Zinc Copper , Mercury Symbols, K... Na Ca Al Mg Mn Fe Pb Zn Cu Hg Comb No. Silver Ag Gold Platinum. Au Pt 39 23 20 13.7 12.6 27.5 28 104 32.5 32 100 108 98.5 5 41. Fourth LAW.-rAe combining number of a compound is the sum of the combining numbers of its components. 42. This law follows as a necessary result of the law of equivalent proportions. It is proved both by analysis and by synthesis. Thus, bv synthesis-.to saturate 47 parts by weight of Potassa, or 116 parts by weight of Oxide of Silver, there are required 40 parts of Sulphuric Acid, or 54 parts of Nitric Acid, or 75-5 parts of Chloric Acid, or 167 parts of Iodic Acid, or 51 parts of Acetic hav«J^.!,T^^^'*"^*'^8*^"*^^«*»^^« «o that the student micht have collected in small compass the symbols Pomh!„,-„„ ^,:^Z^ T^l the elements most commonly met with " ""' "'° «"'"5h.", «c, ot OinBMIOAL OOMBWATION. 15 Now 47 pwt8JCO==ono oqulvalont JC. 89+ ono equivalent 0.8 and 39+8 = 47 = Combining Number of KO. 116 parts ^^0 = one equivalent J«. log+one equivalent 0. 8 and 108+8 = 116 = Combining Number of AgO. 40 parts ^03 = one equivalent 8, 16+three equivalents 0, 24 and 16+24 = 40 = Combining Number of SO3. 84 parts NO, = one equivalent N, 14+ Ave equivalents 0. 40 and 4H14 = 64 = Combining Number of NOn . 75-6 parts CTO5 =oneequivalontCT.g8-8+nve equivalents 0, 40 and 40+38-6 = 78 8 = Combining Number of ClOn . 167 parts /Ofl = one equivalent /, 127+flve equivalents O, 40 and 40+127 = 167 = Combining Number of /Oa , 51 parts Acetic Acid = four equivalents of C. 24+threo of H, 8+three of 0. 24. and 24 + 3 + 24 = 61 --= Combining Number of Acetic Acid. Thus the combining number of the compound is in every case equal to the sum of the combining numbers of its constituents. The same may be proved by taking any acid and finding by experiment the amounts of different bases required to neutralize it. 43. Whm acids combine chemically, union invariably takes place either between equal volumes or between volumes which bear a simple relation to each other. 44. This is not only true of elementary gases, but also of compound gases and the vapours of volatile liquids, when they unite among themselves. 45. The ultimate reason of this law may be found in the very remarkable relation existing between the specific gravity of a body in a gaseous state and its chemical equivalent, viz.: Quantities by weight of the various gases which combine, occupy (temperature and pressure being equal) cither equal volumes or volumes bearing a simple relation to each other. Thus 8 grs. of occupy (6O0 Fahr. and 30 in. Bar.) 23'3 cu. in. 1 " H " " " 46-7 u 35-5 " CI « u ti 4g.2 « 127 grs. vapour of / " « u ^q.,j „ That is, equivalents of H, CI, and / occupy equal volumes, and of O half a volume. ' 40. If both the specific gravity and the chemical equivalent of a gas be kuown, its equivflient oi- combining volume can r 16 EQUIVALENT VOLUMES OF OASES. easily be determined, since it will be represented by the number of times the weight of a unit of volume (the spec, grav.) is con- tained in the weight of one chemical equivalent of the substance ; i. e., the equivalent volume of an element is found by dividing its chemical equivalent by its specific gravity, and comparing the quotient with that obtained in the case o/H. Substance. Hydrogen Nitrogen Chlorine Bromine Vapour Iodine Vapour Carbon Vapour Mercury Vapour Oxygen Phosphorous Vapour Arsenic Vapour Sulphur Vapour Water Vapour Protoxide of Nitrogen Sulphuretted Hydrogen Sulphurous Acid Carbonic Oxide Carbonic Acid Light Carburetted Hydrogen. OleflantGas Binoxide of Nitrogen Hydrochloric Acid Phosphoretted Hydrogen Ammonia Ether Vapour Alcohol Vapour Benzol Vapour Sp.grav, 0.0693. 0.972... 2.470.., 6.895... 8.716.. 0.418.. 7.000.. 1.106.. 4.360.. 10.420.. 6.654.. 0.625.. 1,525.. 1.171.. 2.210.. 0.973.. 1.524.. 0.659. 0.981. 1.039. 1.269. 1.240. 0.589. 2.686. 1.613. 2.738. Equiv. weight. 1.0. 14.0. 35.5. 80.0.... 127.0.... 6.O.... 100.0.... 8.O.... 32.0.... 75.0.... 16.0.... 9.0. ... 22.0... 17.0... 82.0... 14.0... 22.0... 8.0... 14.0... 80.0... 86.6... 85.0... 17.0... 87.0... 46.0... 78.0... Equivalent volume. 14. 48 or 1 14. 87 or 1 14. 38 or 1 14. 82 or 1 14. 67 or 1 14. 34 or 1 14. 29 or 1 ^ 7. 23 or i 7. 35 or i 7. 19 or i 2. 40 or ^ 14. 40 on 14. 43 or 1 14. 61 or 1 14. 52 or 1 14. 39 or 1 14. 43 or 1 14. 31 or 1 14. 27 or 1 28. 87 or 2 28. 70 or 2 28. 22 or 2 28. 86 or 2 14. 81 or 1 .52 or 2 28. 49 or 2 Thus it appears that H, N, CI, Br, I, C, and Hg, in the state of vapour, have the same equivalent volume ; O, P, ^«, one half of this ; Sulphuric Add, one sixth, &c. Note.— The slight discrepancies in the third column result chiefly flrom errors in determiulug the specific gravities. ^ NOTATION. 17 svdt chiefly from NOTATION. 47. The symbol of an element standing alone signifies 1 atom or equivalent of the element. Thus H stands for 1 atom or equivalent of Hydrogen, Ft fop 1 atom of Iron, &c. 48. A symbol with a small figure below and to the right of it signifies as many atoms of the element as the figure expresses. ' Thus Og means two equivalents oi 0\ 8^ means fire of sulphur, &c. 49. Symbols joined by the sign +, or simply placed together, signify a compound of 1 atom of each element. Thus H-\-0 or HO = Water, a compound of 1 atom of H and 1 of 0. 50. If a small figure be attached, as above, to either or both symbols, it multiplies that symbol only to which it is attached. Thus MnO^ = Binoxide of ilf/i = 1 equivalent of Un and 2 equivalents of O. So also Fe^O^ — Sesquioxide of Iron = 2 equivalents of Fe. and 3 equivalents of O, &c. 51. When a compound formed by the union of two or more compounds is to be expressed, the compounds which combine are joined either by the sign + or by a comma. Thus HO-i-SO., or ffO,^©, signifies Hydrated Sulphuric Acid = 1 equivalent of water and 1 equivalent of dry SO3. 52. A large figure placed on the same level as the symbol and to the left of it, multiplies every symbol as far as the next comma or n«xt + sign; or it multiplies all within brackets if placed before them. Thus 2H0 = 2 equivalents of Water = 2H + 20- 2S0^,K0,H0 = Bisulphate of Potash = 2 equivalents of 80^, 1 equivalent of KO and 1 equivalent of HO. But 2(S03,KO,HO) or 2(503+^0+ HO) = 2 equivalents of a compound which is formed of 1 equivalent of SO^j 1 equivalent of KO, and 1 equivalent of HO. 53. Thfi fnllnwincr ara anrna aimn^^l^.^ -v* _i •_-. <• . . . — jj, »i„ „v,av v^«iii|^iCB ui vuuxuiCtii IGHuUlaS : 18 Alum Sugar Alcohol Acetio Acid Morphine CHEMICAL AFFINITY. = M,0,,3SO,-\-KO,SO,+2\HO. Acetate of Morphine= C^^Hi^NO^yC^HiO^. 64. Sometimes, in order to show the new arrangement of the elements in chemical combinations, we make use of the equation. Thus, KO+HCl = HO-^KCL CHAPTER in. CHEMICAL AFFINITY. 66. Elements which are capable of chemically uniting are said to have an affinity for each other. ,. , ,.^ ^^„, • This power of union or aflanity is exceedmgly different m degree among various bodies, and is much modified by a number of circumstances. 66. As a general rule, the more unlike any two bodies are in chemical properties the stronger is their aflBnity for each other Thus the metals have a strong affinity for oxygen and chlorine , the bases, a strong affinity for acids, &c. 57. Chemical Affinity may be defined to be that force or at- traction by which the particles of two or more dissimilar bodies unite to form a compound which is totally different in its chemical nature from either of its constituents. 68. Affinity is either simple or elective. 69. Shnple Affinity is that force by which two or more/ree bodies become chemically united. EXAMPLES OF SIMPLE AFFINITY. r uniting are bodies are in bv each other, and chlorine ; it force or at- isimilar bodies ifferent in its = Vermilion. CHEMICAL AFFINITY. 19 3 Oxygen > _ ^ Chlorine ) « ^- Hydrogen J - ^**®'- 4. g^^.^^ J Common Salt. 6. Oil > a Oxygen i Potash S — ^°^P* ^' Hydrogen > = Sugar. Carbon ) 60. Elective AflBnity is either single or double. 61. Single Elective Affinity involves a single decomposition ; i. e., it enables a body, J, to elect or choose another, B, which ig combined with a third, C, which third, C, is always set free. BXAHPLBS OF SIMPLB BLBOTIVH APKNITT, No. 1. ( Acetic Acid Acetate of Lead / ( Lead Zinc No. 2. Acetate of Lead. Sulphuric Acid. Acetic Acid- Lead. Lead Acetate of Zino. -Acetic Acid. =Sulphate of Lead. Sulphate of 5 ^'^^P^^"<^^c^^- ^°PP^' ^Copper. No. 3. -Sulphuric Acid. Ammonia, rAmmonia-salt of Copper. No. 4. I Sulphate of 5 Sulphuric Acid ^°PP^^ I Copper ITrnn Copper ouipuuiu ux iron. n %o OHIMIOAL APFINITT. ]fo. B. -.. * * C Nitric Acl iriimte of S Mercnry ^ Mercury Oopp< { <...^ftd Acetate of Potassa. niii>nm^ . ^ ,^ Sesquioxide of Mn=Mn^O 3, a feeble base. $ ^^^^^ Oxides. Deutoxido o{Mn=:MnO^, neither basic nor acid. 5 o^^.f*"°* Manganic AcidrriJfnO,, a strong acid. ( xi e. ^^Permanganic Acid=ifn,07, a very strong 5 Acid Oxides. From this it may be inferred that in a family of oxides of an electro-positive body, the most powerful base is that containing one atom of O; and that as the quantity of increases, the oxide passes from basic to indifferent, and, finally, from indifferent to acid. 113. Combustion may be defined to be " chemical combina- tion attended by light and heat." Ohas been termed a supporter of combustion, as distinguished from a combustible body, such as P. But we aie not to suppose that the G has any greater or any different share in the combustion than the P. It so happens that the O is a gas whUe the P is a solid. Heat and Ught therefore appear to proceed from P alone, because the combustion or chemical combination can only take place where the two bodies are in contact. In reality, both bodies are equally concerned in the production of light and heat ; and we may with equal accuracy consider O a combustible and P a H_^ ... „. . ^.uxuuatiuu, »s ^ a comDUdtibie aud O a supporter of com- OXYaiN. B^ Oxidea. the batic Ex. KOi InO^ &c. I'ttgO, &c. uatration [dos. idiff«rent xide. Oxides. es of an ntaining the oxide ferent to lombina- id from a the G has >P. It so therefore chemical itact. In light and e and F a r of com- Itt all combuitlon in our atnio«phore, the hea. and light, at above explained, appear to proceed ft-om what is called the combustible or burning body because it is solid or liquid, or, if a gas, issues from a Jet and is •unrounded by an atmosphere conuining O, which can only act on the combustible at the surflace of tho latter. But this is merely appearance j for while a jet of // burning In a jar of O appears to give out the light and the heat, a Jet of O burning in a jar of If seems equally to be tho source of heat andjlight, which, in both oases, proceed from the combination of the O andJSr. If our atmosphere consisted of Coal Gas, we should have to search, not for coal to burn in It, but for substances capable of yielding O, such as Manganese, Chlorate of Potash, Ac. lU. Many substances slowly unite with 0, without the visible manifestation of light and heat, as when iron rusts or wood decays in the air. H6. First Law or CoiiBtrsTiON.— .>« given amount of a com- bustible body when burned, will always furnish a constant amount of heat, whether the combustion occupies only a few moments or lasts during many years, He. SaooND Law of Combustion. — The amount of Heat evolved bears a close rehtion to the amount of O consumed. Thus a lb. of O combining with B, or with charcoal, or with alcohol, develops nearly the same amount of heat in each case, and will raise 29 lbs. of water firom 82" F. to 212° P. The amount of heat evolved by equal weights of different combustibles combhiing with O, is as follows : 1 lb. of Carbon raises 78 lbs. of water from 32" to 212" F. " Alcohol " 68 " " •« " OilorWai" 90 " " •• . " Hydrogen " 236 " " '• Now 1 lb. of C combines with 2* lbs. of O, and 1 lb. of iJ combines with 8 lbs. of O; that is, H consumes three times as much as C consumes, and consequently gives about three times as much heat. 117. The elements of most substances used for illuminating purposes are chiefly Hand C. The affinity of for ^is superior to its affinity for C ; it therefore seizes upon the H first, burn- ing it with intense heat, the solid C being at the same time set free. The particles of the C being thus heated to lumi- nous whiteness, produce the light which is emitted from th« name. The luminous particles of C floating forward, as they 36 HTDROQEN. are liberated, to the surface of the flame, come in contact with the of the atmosphere and pass off as Carbonic Acid while the H is converted into water. 118. When the burning body contains both elements but a dis- proportionate amount of C, as in Spirits of Turpentine, more of it is set free than can be consumed by the O, and the flame smokes. When the H is in excess, as with Alcohol, there is much heat but little light and smoke. When mingled, these fluids correct each other's defects, and form the basis of " burning fluids." 119. Common flame is not, as it appears, a solid cone of fire, but a hollow luminous shell. This may be shown by holding a piece of metallic wire-gauze over the flame. The dark central portion is constantly filled with gases formed from the tallow or oil by heat. A portion of these gases may be conveyed away by a glass tube and ignited at a distance from the flame. 120. In the common flame, several parts may be distinguished thus : Fig. 2. I. A faint bluish exterior cone, a, where the com- bustion is complete. II. A bright luminous inner cone, c, consisting chiefly of particles of C intensely heated. III. An interior dark mass, b, consisting of uncon- sumed gases. LECTURE VI. HYDROGElf. 121. Hydboobn. Symb. H] Equiv. 1 ; Comb. vol. 1 ; Spec Grav. 0.0694; 100 cubic inches vf^eigh 2.14 grs. lOQ XT la i}ta 1i/yVi4-acif n^ oil IrnATtrn anVka^atmaa ifd TxrAiivlif l\Ainr* only one sixteenth that of atmospheric air. HYDROGEN. 37 tact with cid while but a dis- more of it e smokes, luch heat is correct luids." )f fire, but ig apiece ith gases lese gases i distance inguished Fig. 2. 1; Spec 123. /f when pure is without color, taste or smell, (the odor pertaining to it, as commonly prepared, arises from impureties.) 124. Hia a. combustible but a non-supporter of combustion. If a lighted taper be introduced into a jar of H, the gas ignites directly the flame comes in contact with it and the taper is extinguished by being immersed in the gas. 125. H, when perfectly pure, burns with an almost inrisible flame. 126. Pure H may be bieathed without injury, as it is not poisonous. It nevertheless produces a peculiar effect on the voice imparting to it a shrill squeaking tone. An animal placed in an atmosphere of H would soon die for the want of O. 127. A jet of ^produces musical sounds when burned in glass tubes of different lengths. This Music of Science is proc' ■ -ed by the successive explosions, which, in reality, constitute the flame, causing the air to vibrate within the tube. 128. H has never been reduced to the liquid, much less to ;he solid form, nevertheless many chemists suppose it to be a highly volatile metal. Its gaseous form is no objection to this theory . for mercury and certain other metals are very easily volatilized. 129. Hm&j be prepared from Zn by the action of HCl or H0,S03. Iron filings may be substituted for Zn.* • To prepare Hydrogen for experimental piir- poaes, we obtain a wide-mouthed bottle and pass two tubes through the cork, as in the accompany- ing figure— the upright tube reaching to within half an inch of the bottom of the bottle, and the other merely penetrating through the cork. In this bottle we place an ounce or t% o of »nc clip- pings or iron filings, and about one third fill the bottle with a mixture of 1 part sulphuric acid and 5 or 6 parts water. The gas that first escapes must not be collected, as, being mixed with the O of the air contained in the bottle, it would cause an explosion. The gas issues from the beui: tu.be.Sind ni£^ \ift collsrted ovfi? tlio pneumatic trough in the s^me manner as 0. Fig. 3. 38 HTDROGESr. RB-ACTIONS. HCl \ci -H set free. Chloride of Zinc- Zn — 130. When dilute Sulphuric Acid is used in place of Hydro- chloric Acid the reaction may be represented as follows : ^ j j H set free. Water < Zinc- »OxideofZinc HO.SOi — — Or more probably as follows :— (fi- Water < ^Sulphate of Zinc. -H set free. no,so ^ Water. i=Sttlph. of Zinc. 131. Jf unites with to form water — with CI, Br^ I and Fit forms powerful acids the general formula of which is HM where JHf represents one atom of a metalloid— with C, S, P^ 8e, and Jls it forms combustible gases ; with N it forms Ammonia, and probably two other compounds, Ammonium and Amidogen. BXPERIMBNTS. I. Plunge a lighted tapfir into a jar of H (kept inverted in order to prevent the escape of the fl), the taper is extinguished, but the H takes fire and burns slowly up the inside of the jar. Upon gradually withdrawing the tttper, it rekindles as it passes J.1 . ~t xt,« 1 • tr fitDROGEN. 39 free. de of Zinc- of Hydro- )-ws: ree. iteofZinc. !t free. ter. 3h. of Zinc. I and J?* it Lch is MM 7, S, P, Se, Ammonia, Amidogen. nverted in tinguished, of the jar. %B it passes tl. Mix in a softened bladder one volume of O with two vol- umes ofH, and tie the neck of the bladder tightly. Then, having obtained a lighted taper attached to the end of a long stick pierce the bladdei with the blade of a penknife, and, standing as far oflf as possible, apply the flame to the orifice. The gases instantly combine with a loud explosion and form water. III. Fill an India-rubber gas-bag with H, and attach to the stop-cock a hydrogen pipe for blowing bubbles. Dip the pipe in a strong solution of soap, turn the stop-cock and press the gas-bag. A bubble is thus formed which detaches itself from the pipe, and rises through the air on account of the great levity of H. These bubbles may be exploded by a lighted taper. 132. If two volumes of O and one volume of H be mixed and fired, by electricity or otherwise, water is formed. Indeed water is formed whenever H burns in atmospheric air and if it all be collected it will be found to be just 9 times the weight if the H consumed. t 133. If, in a graduated tube, 210 vols, of H be mixed with 100 vols, of O and the mixture exploded 10 vols, of if will remain unchanged. If the proportions had been 200 vols, of H and 110 vols, of O, 10 vols, of O would have been left. Hence 2 vols, of if unite with 1 vol. of O to form wats^r. 134. Water may be analyzed by Galvanic electricity. Thus when the electric current of a powerful battery is made to pass through water in an apparatus so contrived that the gas given oflf at each electrode is received into a graduated tube it is found that when the tube at the positive electrode is half full, the tube at a negative electrode is quite full ; and on examination, the gas in the latter is found to be pure H while that in the former is pure 0. The proportion by volume is evidently 2 of if to 1 of and by means of the Specific Gravities of gases we obtain the proportion by weight of 1 to 8. WATER* 135. Water, symbol ifO, equiv. 9, i^, at ordinary temperatures, a colorless- tasteless and inodorous li^^uid • assutnfis the s^lid form at 32" F. and becomes gas, steam, or vapour at 212" F, 40 H7DB0OEN. 136. The point of greatest density of water is 39'2o F. The specific gravity of ice is 0'92. 1 cubic inch of water expands into 1 cubic foot of steam. 1 cubic foot of water weighs 1000 ounces avoirdupois ; one gallon weighs 10 lbs. 137. "Water is the most powerful solvent known, acid nor basic but is perfectly neutral. It is neither 138. The compounds of water with acids and bases are called hydrates; as HO,SO^f hydrated SO3, HO,KO, hydrated KO, &c., to distinguish them from anhydrous SO3, anhydrous KO, &c. 139. The combination of water with other bodies is often attended with much heat. Ex. HO and SO3 ; CaO and HO. 140. Water combines with neutral salts in two conditions. In the one it is easily expelled by heat, and the salt, if crystallized, falls to powder. This is called water of crystallization, and its quantity is often very great ; as for example, in Alum, which con- tains 24 equivalents. In the other, a portion of water, genemlly 1 equiv. is combined with the salt by so powerful an affinity as to be with some difficulty separated. This is called saline water. In fonnulao water of crystallization is sometimes represented by aq. and saline water by HO, Thus : green vitriol is represented as follows. FeO, SO3+ JffO-f-e aq. That is, 1 equiv. of sulphate of protoxide of iron, 1 equiv. of saline water, and 6 equiv. of water of crystallization. When this salt is gently heated the 6 equivalent of water of crystallization are expelled, but the 1 equivalent of saline water can only be expelled by a red heat. 141. The solvent power of water is generally increased by heat, so that a hot saturated solution of any salt usually deposits crystals on cooling. There are a few remarkable exceptions to this law. Thus : common salt is nearly equally soluble in water of all temperatures, and certain organic salts of lime dissolve mt ve freely ii cold than in hot water. 142. Water also dissolves, combines with or absorbs, as it is called, many gaseous bodies. The gas, In this case, is supposed •2»F. The spands into .000 ounces tis neither i are called Irated KO, lus KOy &c. 13 is often md HO. ditions. In rystallized, on, and its which con- , generally finity as to line water, esented by epresented jf sulphate 6 equiv. of if water of iline water creased by ly deposits eptions to ie in water e dissolve bs, as it is i supposed IITDROOEN. 41 to assume the liquid state, and as heat tends to cause bodies to assume the gaseous form, it is obvious that heat must diminish and cold increase the solvent power of water for gases. In- creased pressure also enables water to absorb more of a gas than it would do under ordinary circumstances-— evidently because pressure favors the liquifaction of a gas by forcing the particles into closer contact. 143. A small portion of any one gas dissolved in water generally very greatly diminishes its power of dissolving other gases. 144. The proportion of different gases taken up by water is very variable. In its natural state it absorbs of Hydrogen, 1-6 per cent of its volume. Nitrogen, 1'6 " " Oxygen, 40 " " piefiantGas, 12-5 " " Carbonic Acid, 100-0 " " Hydrochloric Acid Gas an amount = 480 times its volume. Ammonia " = t80 " 145. In consequence of the great solvent power of water it is never found pure in nature. Even rain water, which is the purest, always contains traces of CO 2, NH^, and sea-salt. When rain water has filtered through the soil and reappears as spring or river water, it is always more or less charged with various salts derived from the earth, such as sea-salt, g^ psum, and lime. 146. When the proportion of this dissolved salt is small, the water is called soft ; when large, it is called hard water. 147. Hard water is usually preferred as a drink — the mineral salts dissolved in it and its free carbonic acid gas impart to it a slight but agreeable taste. It is not, however, as healthy a beverage as soft water, and is much inferior for all domestic purposes, as tea or coffee making, or where solution is to be effected, since it is already partly saturated and dissolves addi- tional substances but imperfectly. 42 NITROQEN. 148. When water becomes so highly charged with foreign matters as to have an unpleasant taste or to acquire medicinal virtues, it is called mineral water. 149. Of mineral waters there are several kinds, as chalybeate waters, containing Iron ; sulphurous waters, containing Sulphur ; acidulous waters, containing free Carbonic Acid gas ; alkaline waters, containing the Carbonates of Potash and Soda ; and saline waters, containing neutral salts generally, as Sea-salt and Sulphate of Magnesia (Epsom salts). 150. The only way to obtain perfectly pure water is by distillation. 151. Water plays a most important part in nature. It is one of the chief mechanical agents in the disintegration of rocks, as it enters the crevices and there, freezing, bursts, by its expansion, the fragments asunder. Both gases and minerals enter the roots of plants dissolved in water. It forms the bulk of sap } it constitutes 80 per cent, of the blood and 74 per cent, of the flesh of animals, and is the natural beverage of all adult creatures. DBUTOXIBE OF HYDROGEN OR OXYGENATED WATER. 152. Hydrogen forms a second compound with O, termed Deu- toxide of Hydrogen^ Symb, HO^ = 17. It is syrupy liquid, of a disagreeable odor, and a nauseous, bitter, astringent taste. It is not frozen by intense cold. It is easily decomposed, often with an explosion, and sometimes with a flash of light. LECTURE VII. NITROGEN. 153. Nitrogen. Symb. N ; Equiv. 14 ; Comb. Vol. 1 ; Spe- cific Gravity, 0-9722. 100 Cubic Inches weigh 30*1 grs. 154. Nitrogen is obtained most readily by the action of burning phosphorus ou a portion of air couuued over wale;'. NIIROaSN. 43 th foreign medioinal chalybeate J Sulphur ; ; alkaline loda; and la-salt and .ter is by- It is one of }cks, as it expansion, enter the of sap} it )f the flesh reatures. rmed Deu- quid, of a taste. It scd, often I. 1 ; Spe- cs. action of rtjr wate**. The phosphorus unites with the 0, forming phosphoric acid, which is absorbed by the water, and nearly pure Nitrogen left. 166. iVmay also be obtained by causing a current of chlorine gas to pass through a solution of ammonia in a proper apparatus and with due caution. 166. Perfectly pure JVmay bo obtained by heating a concen- trated solution of Hyponitrite of Ammonia, the reaction being as follows :— Ammonia Water . Hyponl trous acid J equlv. water. 2 equiv. water. A N. sot firoc. 167. Nitrogen was discovered by Rutherford in 1TT2 ; and was called Azote or llfe-depriver. It was afterwards called Nitro- gen, from its being one of the ingredients of Nitre or Saltpetre. 168. iV is a colorless, transparent, permanently elastic gas ; has neither taste nor smell ; has uo action on colored tests ; is a perfect non-supporter of combustion, and is chiefly distinguished for its negative properties, i. c. It exhibits no tendency what- ever to enter into combination with other substances. 169. Almost all the compounds of N are very easily decom- posed, and many of them are even dangerous from their tendency to explode from very slight causes. The most important com- pounds of ^ are those with and H. 160. Nitrogen forms an important constituent of atmospheric air, which is a mechanical mixture chiefly of nitrogen and oxygen. NoTH.— The N in the atmosphoro servos the purpose of diluUng the 0, 44 NITBOOBN. lei. The composition of the Atmosphere is as follows : BY WHiaHT, BT MEASUBB. Nitrogen- 77 parts. 79-19 > . « , . ^ Oxygen, 23 « 20'81 5 ^'^ * ^ *^<^ * ^• Carbonic Acid, from 4 to 6 parts in 10,000. Light Oarburetted Hydrogen " " " Aqueous vapor, variable. Ammonia, a trace. 162. The amount of O in atmospheric air may be measured in several ways. I. By passing air through a tube containing pure metallic spongy copper heated to redness. The copper combines with the 0, and the iV^is collected and weighed. The loss of weight gives the amount of 0. II. By placing a stick of phosphorus in a graduated tube containing a known quantity of air standing over water. The O is slowly absorbed and the loss of volume gives the amount of O. III. By explosion with the Eudiometer. A known volume of H is introduced into a known volume of Atmos- pheric air and exploded. One third the loss in volume being the O. Figure i represents the Siphon Eudio- meter of Dr. Ure. This consists of a bent glass tube havmg a bore of about one-third of au inch in diameter. The tube is open at (me end and closed at the other, and near the top of the closed limb two plati- num wires are melted through the glass, so as nearly to touch one another within the tube. Finally the closed limb of the Eudiometer is cwefully graduated. Wlien required for use the instrument is filled with mercury, and the portion of air to be examined is then introduced into the closed limb. The mercury is now adjusted so as to have the same level in each limb, and the quantity of air introduced measured by the graduated scale. As nearly as possible half as much Hydrogen is then introduced and the level Fig. 4. NITROGEN. 45 of the mercury again adjusted. One of the platinum wires is now con- nected with the outside C a charged Leyden jar, and, having first closed the open end of the Eudi ^moter with the thumb or with a tight cork, an electric spark is passed Through the confluod gas and air. The J7instantly unites with the O, and the mercury rises in the closed limb. Thus : suppose Air introduced Hydrogen 100 measures, 80 " Air and Hydrogen = 160 " Volume^ after explosion = 87 " Loss of Volume =: 63 " Then 63 -f- 3 — 21 = measures of O in 100 measures of Air. 163. 100 cubic inches of Atmospheric Air, under the usual conditions weigh about 31 grains. 164. The of the air is constantly consumed by Animals. The exhalations from the skin and lungs of a single human being vitiate or spoil for breathing 10 cubic feet per minute or 00,000 gallons of air per day. Also combustion removes O and in both cases the result is carbonic acid gas which is poisonous to ani- mals. On the other hand plants constantly absorb carbonic acid and exhale O. Thus plants and animals mutually prepare the air for supporting each other's life. 165. The Atmosphere is partly kept pure by the remarkable law of gaseous diffusion. Thus if two bottles connected by a tube and stop-cock be placed one over the other, and if the upper be filled with any light gas, and the lower with a heavy gas, and if the stop-cock be turned so as to allow a communication to exist between the two bottles, in a short time the gases will be found to be intermixed. That is, in opposition to the law of gravity, the light gas descends and the heavy one rises and the two intermingle, COMPOUNDS OP NITROGEN WITH OXYGEN. 166. NiTEOus OxiDB ; Pbotoxidb.op Nitrogen ; Laughing Gas. Symb. NO =: 22. Is a colourless, transparent gas; has a faint smell and a sweetish taste ; is slowly absorbed by water ; Spec. Grav. 1'52 T ; is prepared by applying a moderate heat to pure 40 NITROGEN. Nitrate of Ammonia, and may be collected over tepid or warm water ; liquifies at 0° und6r a pressure of 30 atmospheres ; sup- ports flame ; is not poisonous but produces a remarkable effect when inhaled. 167. Nitric Oxide ; Dbutoxidb ov N; Nitrous Gas. Symb. iVOg = 30. Is a colorless, transparent gas ; seizes when in contact with air and forms red fumes of nitrous acid gas ; best obtained by treating copper clippings with dilute nitric acid ; is collected over water ; extinguishes some flames but supports others. Spec. grav. 1-041, — has no action on colored tests. 168. Hyponitrous Acid. Symb. NO^ = 38 ; is obtained with difficulty ; is a very volatile liquid, which is colorless while cold, but at ordinary temperatures becomes green ; combines with bases to form hyponitrites ; reddens vegetable blues. 169. Nitrous Acid ; Hyponitrio Acid. Symb. NO^ = 46. Is obtained by mixing one vol. of with 2 vols, of dry Nitric Oxide in an exhausted receiver ; is a deep red vapour, condeu- sible to an orange liquid at O", and solidifiable at a lower temperature. The liquid boils at 82°, and has a spec. grav. of 1-45, that of the vapour being 3-19. NO^ is an acid, but does hot form salts with bases, being decomposed and hyponitrites and nitrates formed ; reddens blue tests. 170. Nitric Acid. Symb. NOo = 54. This most impor- tant of all compounds of N and O has recently been ob- tained perfectly anhydrous. The hydrate i? best obtained by distilling a mixture of equal weights of hydrated sulphuric acid and of nitre or saltpetre (i. e. nitrate of potash.) Nitre. Eb-aotion. ( Nitric Acid ^;;::::^Hydrated Nitric Acid. ( Potassa_ Hydrated ^ Water Sulphuric 7 Aftirl. . . / Siilnlmri Inlmrift Ao.id- -Bisulnhate of Potassa. NITROaBN. 47 171. Nitric Acid is a colorless, intensely acid liquid ; spec, grav. 1'46; a powerful deoxidizer; combines with bases to form nitrates, reddens blue strongly, exists in nature as Nitrate of Potash, &c., formed in the air by electric sparks and flashes of lightning ; is used in the arts to oxidize and dissolve motals ; is of great importance in dying, metallurgy and medicine. COMPOUNDS OF NITROGEN WITH HYDROOBN. 172. Nitrogen is supposed to form three compounds with H, viz. : Amide or Amidogen, Ammonia, and Ammonium, of which Ammonia alone is known in the separate state. 173. Ammonia ; Volatile Alkali ; Spirits of Hartshorn. Symb. NHj = IT, occurs in nature in the urine of animals as urate of ammonia ; in combination with HCl as sal-ammoniac ; and in the air as a constant result of the putrefaction, decay and combustion of organic matters containing JV. Ammonia, was formerly obtained from the destructive distillation of horn, and was hence culled hartshorn. It is a transparent and colorless gas, which is converted into a liquid by a pressure of about 6 J atmospheres, and is similarly condensed by a temperature of 40° P. ; by a very intense cold it is frozen to a white crystal- line mass ; it has a powerful and peculiar pungent smell and taste; is strongly alkaline, and is hence called the volatile alkali ; acts powerfully on colored tests ; is obtained by heating sal-ammoniac with quick lime ; is slightly combustible but is a non-supporter of flame ; its spec. grav. is 0*5902 ; readily combines with acids to form salts ; water absorbs "780 times its volume of ammonia and forms aqua ammoniso. 174. Amide or Amidogen. Symb. NHg = 16. A hypotheti- cal compound ; has never been obtained separately, but is sup- posed to exist in combination with metals, as Amides, and in organic Compounds. 176. Ammonium. Symb. NH4 = 18. Is also a hypothetical compound, i. e., does not exist in a separate state but is snppo- sed to exist in an independent state in some of the compounds of Ammonia, as a metal NH4 or as an oxide NH4O. 48 CABBON. LECTURE VIII. CARBON. 170. Carbon. — Symb. C; Equiv. = G; Comb. vol. of (hypo- thetical) vapour = 1. Name from carbo, a coal. Exists in three allotropic states. 177. I. Diamond— found in India, Borneo, Brazil, &c.; crystal- lized in regular octahedrons ; is sometimes coloured, but the transparent is considered the most valuable; is the hardest sub- stance known ; infusible, but is combustiblo at a white heat ; can only be polished or cut with its own dust; is used as a gem, also for cutting glass and for pivot rests in delicate machinery, as watches, &c. Diamonds are sold by the carat (3-2 grains), and they increase in value in proportion to the square of their weight. The average value of a wrought diamond of one carat is $40, therefore value of one of 2 carats = 40 X 4 = $160, one of 10 carats = 40 X 100 = $4000, of 100 carats = $400,000, &c. The largest known diamond is probably the " Kooh-i-Noor " (mountain of light) which was discovered in the minet^ of Gol- conda three hundred years ago, and is said when rougu o have weighed 900 carats. It has been reduced by cutting vo 2*79 carats, and although never sold is said to be worth $10,000,000. It has caused several wars, and has been six times violently wrested from its possessors. It now belongs to the crown of England. If a piece of diamond and a piece of pure soft iron be sealed together and exposed to an intense heat the iron is converted into steel, thus proving tl e diamond to be carbon. Diamond is, in fact, the purest kind of C. 178. II. Graphite — Plumbago — Blacklead — is the second allo- tropic form of C. This rarely occurs in crystals which are six- sided prisms. It is sometimes rendered impure by containing iron which varies in quantity from a trace up to 5 per cent. It resists a very intense heat, and is therefore used for making crucibles, also used to diminish friction, and iu the manufacture of black lead pencils. OARBON. 49 179. III. Lampblack and charcoal arc examples of the third allotropic form of C. In this state it is amorphous. 180. C, as diamond, is a non-conductor of electricity, while as graphite or charcoal it forms an excellent conductor. 181. Charcoal — is obtained from burning organic matter (wood, bones, etc.,) out of contact with air; appears to be softi but the fine particles are exceedingly hard, and easily scratch glass ; is used for fuel ; when pure burns without flame ; is very indestructible, charred stakes remain centuries buried in the earth without decomposing; the most important property of charcoal is its absorbent power ; absorbs 90 times its bulk of ammonia, 35 times its bulk of carbonic acid gas, 9 of O, and 7 of N] also absorbs a large quantity of water ; a cubic inch of char- coal id supposed to possess 100 square feet of surface ; from its absorbent capabilities arise its antiputrescent and disinfecting powers ; newly prepared charcoal at once sweetens tainted meat or fish ; the inside of casks is charred in order to preserve water ; charcoal is used as a filter ; from its absorbent power also arises the great value of its action upon soils. 182. Carbon exists native in the Diamond, Graphite, &c. — and is also found in combination with many of the other ele- ments, as Carbonate of Lime, Marble, Chalk, or Limestone ; Car- bonate of Magnesia, Carbonate of Br ,,, u. ibonate of Strontia, Carbonate of Lead, &c. It is au essential ingredient of all organized tissues and products, animal and vegetable. 183. Animal matters whcD burned yield animal charcoal, which contains phosphatep Charcoal from bones is termed bone-black or ivory-black, and is of course loaded with phos- phate of lime 5 it is, however, the best of all decolorizers. Oils and resins burned with deficiency of O, yield lampblack, which is nearly pure C. COMPOUNDS OP CARBON AND OXTGEN. 184. Carbon unites with O to form several compounds, the most important of which are Carbonic Oxide, Oxalic Acid, and tio CARl^ON. 185. Caebonio Oxidb, Symb. CO = 14, Spec. Gravity 0-972, is obtained by heating in a retort 1 part of finely powdered ferro- cyanide of potassium with ten parts of oil of vitriol ; may be col- lected over water; is transparent and colorless; has neither taste nor siuell ; is poisonous when respired ; extinguishes flame but burns itself with a clear lambent blue flame, generating carbonic acid ; is a compound radical. 186. Carbonic Acid ; Fixed Aiu ; Mbphitic Gas ; Choke Damp. Symb. CO^ = 22 ; Spec. Grav. 1-52 7.— Exists in the atmosphere ; is formed by combustion, respiration, fermentation, decay, and volcanic action ; exists also in Carbonates of Lime, Magnesia, Iron, Oopper, &c. 187. Carbonic Acid may be formed by burning any of the forms of carbon in air or in O, or by decomposing a carbonate by more powerful acid ; it may be collected over water with consi- derable loss, or by simple displacement. 188. COi is a transparent, colorless gas ; soluble in water ; poisonous if respired ; a non-supporter of combustion ; liqui- fies under pressure of 40 atmospheres, and when the pressure is suddenly removed, a portion abstracts heat and becomes gas, the remainder becoming a solid, like snow, which when dissolved in ether and allowed to evaporate, produces the most intense cold known ( — 200o F.) ; a bottle of mercury of several pounds may be frozen in a few minutes if placed in contact with this mixture. The acid powers of CO^ are so very feeble, that it scarcely reddens blue tests ; combined with bases, it forms car- bonates, and it is expelled with effervescence from these com- pounds by every other acid, except hydrocyanic. It is essential to the growth of plants, and is employed in the manufacture of the various carbonates and of effervescing mineral water ; causes stupor and finally death if mixed with air even in the proportion of 1 to 10 ; is exhaled from fissures in the earth in volcanic countries, as, for example, in the Grotto del Cano, the Valley of Death, &c. XO{7. V^aliiU XXUll/, VJjlU.U. ■«--gVJ"3 i mes gas, dissolved t intense il pounds with this e, that it arms car- lese com- sential to ire of the * : causes roportion volcanic Valley of att^^r^r^ nn "" © 8ts native 111 rhubarb, sorrel, and many other plants ; has not been obtained independent of water or a base ; the hydrate is a white crystal- line solid, subliming at about 300o F ; soluble in water ; strongly acid ; reddens vegetable blues ; combines with bases to form oxalates ; is very poisonous (antidote chalk or magnesia). 100. The other compounds of C and O are Croconic Acid, CsO^-\-HO] Rhodozonic Acid, C^0j+3H0, and Mellitic A 'id, C4O3+HO. COMPOUNDS OP CARBON AND HYDUOGBN. 191. The compounds of C with H are very numerous, and belong chiefly to organic chemistry. The most important hydro- carbons are Light Oarburetted Hydrogen, defiant Gas, Gutta Percha, Caoutchouc, Naphtha, Camphene ; and the hypothetical hydrocarbons, Methyle, Ethyle, Amyle, Acetyle, &c. 192. Light Oaeburbtthd Hydrogen, Marsh Gas, Fire Damp, Symb. CHg = 8, Spec. Grav. 0*555 ; 100 cubic inches weigh 17*4 grains ; produces the bubbles arising from pools of stagnant water ; is obtained in the laboratory by heating a mixture of 40 parts crystallized acetate soda, 40 parts solid hydrate of potassa and 60 parts of quick-lime in powder ; it may be collected over water ; is a colorless, transparent gas ; extinguishes flame, but burns itself with a light yellow flame ; when pure is nearly desti- tute of smell ; is not acted upon by chlorine in the dark ; forms an explosive mixture with common air, 2 volumes of O, or 8 volumes of air to 1 of gas, most explosive ; this is the fire damp of mines 5 miners not killed by the explosion are mostly suflFo- cated by the choke damp or after damp (CO^) formed by the explosion thus— Cifg + O4 = CO^ + 2H0. NoTK.— Cfl"2 is not explosive when mixed with less than 6 vols, ov with more than 15 vols, of air. It requires a bright white heat, as flamo, to iRnite the explosive mixture. Davy's Safety Lamp depends upon the fact that metallic wire gauze, having not less than 400 meshes to the square inch, is not permeable by flame. 103. Olbfiant Gas, Heavy Oarburbttbd Hydrogen ; Bioaebidb or Hi C^Hi=z 14 ; Spec. Grav. 0-98 ; 100 cubic inches weigh 31.7 grains ; may be obtained by heating 1 part by weight of Alcohol with 5 or 6 of HO^SO^ ; may be collected over water ; is a colorless gas, which by cold and pressure may be liquified ; 5^ CABBON. when pure has neither taste nor smell ; extinguishes flame, but burns itself with a splendid light ; is the most important consti- tuent of coal or illuminating gas. 1 vol. of 0^11^, mixed with 3 vols, of or 15 vols, of air, explodes with extreme violence ; mixed with its own vol. of chlorine, the two gases rapidly dis- appear and produce an oily liquid, hence the name olefiant; wiien mixed with twice its vol. of chlorine the mixture burns off with a red flame and an immense quantity of smoke, which is carbon, is deposited in the solid form. 104. Coal Gas is obtained from the distructive distillation of bituminous coal in iron cylinders kept at a bright red heat ; the volatilized products are conducted through a horizontal pipe of large dimensions (called the hydraulic main) ; they next traverse the refrigerator or cooler where tar and ammoniacal liquor condense ; the residue is purified from CO^ and sulphu- retted H in lime purifiers and from ammonia by passage through dilute sulphuric acid. 105. Methyle = C^Hs ; Ethyle = C^Hs ; Amyle = C,o»i, ; Acetyle = C^H^ ; are hypothetical compound radicals. 100. Naphtha Cgfla — Mineral Naphtha exists native inJ^'^*^^, Russia, &c. Coal Naphtha is obtained during the destructive iis- tillation of coal ; both kinds are colorless liquids, having a spec, grav. of about 0.800 ; are very inflammable ; dissolve most resins and oils ; are used as solvents for caoutchouc. Mineral Naphtha is also used to preserve potassium, sodium and similar oxidizable tubstances. COMPOUNDS OF CARBON AND NITROGEN. 107. Cyanogbn CiN or Cy is obtained by heating 6 parts of dried Ferrocyanide of Potassium with 9 parts of Bichloride of Mercury. It may be collected over mercury. Spec. Grav. 1*82 ; is a transparent colorless gas, which is rapidly absorbed by water. It may be condensed into the liquid state by a pressure of 4 atmos- pheres, and is then solidifiable by a cold of SO** ; has a pene- trating peculiar odour like oil of bitter almonds ; is highly pob*>; sonous 5 extinguishes 5«*me, but burns itself with a beautiful amc, but at consti- jced with riolence ; )idly dis- olefiant ; burns oflf which is }tillation ed heat ; ntal pipe tiey next [noniacal sulphu- I through r Ciorf]! ; inT^«V/ jti^t iis- g a spec. ist resins N^aphtha ddizable parts of loride of IV. 1-82 ; >y water. 4 atmos- a pene- jhly poi- ^eautiful CHLORINE. 53 purple red flame ; though a compound, it has a remarkable ana- logy to chlorine and to certain other compoundSj such as ammonium. 108. Cyanogen with forms Cyanic Acid CyO; Paracyanic Acid Cy^Oi (fulminic acid), and Cyanuric Acid Cy^O^. 199. Cyanogen with H forms Hydrocyanic Acid or Prussic Acid, HCy, which exists naturally in some plants, and is obtained artificially by distilling Cyanide of Mercury with Hydrochloric Acid or by decomposing it by sulphuretted H^ and condensing the vapour by a cold of 0". It is a transparent colorless liquid, very volatile and solidifying by the cold of its own evaporation. It is highly poisonous ; Spec. grav. 0-700 ; is combustible, burning with a bright flame ; is very prone to decomposition, which is prevented by the presence of a trace of any other acid. Its acid powers are so feeble that it does not expel carbonic acid from carbonates. A dilute solution (97 parts pure water + 3 parts HCy) is cautiously employed in medicine. LECTURE IX. CHLORINE. 200. Chlorine ; Symb. CI ; Equiv. 35*5 ; Comb. Vol. 1 j Spec. Grav. 2-47 ; 100 cub. in. weigh 78 grains ; was discovered by Scheel in 1774 ; name derived from chloros, " yellowish green" ; may be prepared by'heating Binoxide of Manganese with Hy- drochloric Acid, as follows : — C Chlorine _Chlorine set free. Hydrochloric Acid I Hydrogen Oxygen - Manganese Oxygen Hydrochloric J ^^^^"^^ ^^^^ I Hydrogen. Binoxide of Manganese ilfnOg. Water. Chloride of Manganese rWater B 54 CHLORINE. 201. Chlorine may be collected by displacement or over tepid water ;* it is a transparent, greenish yellow suffocating poisonous gas, soluble in cold water, condensible under pressure of 4i atmos> pheres to an oily fluid whose spec. gray, is 1-33. CI has a strong affinity for metals, with which it forms chlorides ; when dry it has little action on veg^ttable colors, but when moisture is present it bleaches them; h % strong disinfectant; its bleaching and disinfecting powers are due to its strong affinity for H which it takes away from coloring and putrescent substances thus decom- posing them ; is very irritating to the lungs when breathed, yet it is said to alleviate symptoms of consumption when respired in very minute quantities. Workmen employed in bleaching establishments and other places where chlorine is used, are said to suffer but little from consumption. CI is said to quicken the germination of seeds. Water absorbs twice its volume of this gas, assumes a green color, and is then called Chlorine Water. EXPBRIMBXTS. I. Dip a roll of paper in turpentine and then place it in a jar of Chlorine. Pig 5 II. Drop some pulverized metallic anti- mony into a bottle of CI. III. Put a small piece of gold leaf into some Chlorine Water. IV. Mix a few drops of Chlorine Water with some ink. v. Introduce a piece of printed calico into some Chlorine Water. • In order to prepare chlorine we obtain a mode- rately large glass flask which we flU to the extent of not more than one-third, with a mixture of 1 meaiure finely powdered black oxide of manganese and 11 or 12 measures of liquid hydrooloric acid. Beneath the flask we place the flame of a spirit- lamp and collect the gas by simple displacement as exhibited in the arrangement represented in the .~»^«i«M 41«mwA CHLOEINE. 55 : over tepid i poisonous )f 4i atmos- as a strong n dry it has ) is present iching and H which it hus decom- eathed, yet en respired bleaching }d, are said [uicken the ime of this le Water. VI. Strongly perfume a handkerchief and drop some Chlorine Water upon it. VII. Drop a piece of metallic sodium into some CI. VIII. Introduce a piece of dry phosphorus into ajar of CI. ' IX. Mix 2 vols, of a with 1 of defiant gas and fire the mixture. X. Mix 1 vol. of CI with 1 of olefiant gas over water. COMPOUNDS OP CHLORINE AND OXYGEN, 202. Hypochlorous acid, CIO, is an orange yellow liquid which boils at 68o, and is obtained by action of chlorine on red oxide of mercury, the reaction being as follows : Chlorine Hypochlorous Acid = CIO. Oxide of r Oxygen Mercury J = HgO. (Mercury- Chlorine- ace it in a 6. I ^ 'Chloride of Mercury = HgCl. The vapour of hypochlorous acid is deep yellow, spec, grav 2-911 ; is readily absorbed by water to the extent of 200 volumes • explodes by heat or by mere contact with many combustible substances, so that experiments with it require the greatest cau- tion ; its solution bleaches powerfully. 203. Chlorous acid, CZO4, is a greenish yellow gas, not liqui- fied by a cold of 5" F., decomposed by light, also by heat of 140« may be made by cautiously acting on small quantities of Chlorate of Potash by Sulphuric Acid with very gentle heat Spec. grav. 2-33 ; explodes furiously from slight causes, the heat of the hand often being sufficient to cause its decomposition. Its smell is peculiar, almost aromatic. Experiment.— Place a little chlorate of potash and a few crumbs of phosphorus in a small jar of water and by means o^ a dropping tube treat it with sulphuric acid, the P burns in the 56 CHLORINE. 204. Chloric Acid, CIOb, is formed when CI is passed through a hot and strong solution of any alkali, as potash ; or when chlo- rate of baryta is dissolved in water and sulphuric acid added so as to exactly precipitate all the baryta as sulphate. ClO^ does not exist independent of a base except in solution which is a thick syrup-like sour liquid, decomposed by a heat of lOQo P. ; forms salts termed chlorates, which are quite permanent but which explode- by friction or percussion when in contact with a com- bustible, as sulphur, phosphorus, or charcoal. 205. Pbuchlobio Acid, ClOj, is formed by the action of oil of vitriol on hyperchlorate of potash. It has not been obtained quite anhydrous, its hydrate is a white volatile crystalline solid, very deliquescent and very soluble in water forming a colorless fuming sour liquid, which has a spec. grav. of 1*65, and which boils at about 400». OOMPOUNDS OF CHLORINE AND HTDROOEN. 206. Hydrochloric Acid, symb. HClj is a transparent colorless gas ; spec. grav. 1*262 ; fumes in the air, absorbing moisture. HCl is obtained by the action of sulphuric acid on common salt. _Cl. Common Salt fO- Sulphuric Acid < H :.NaO,SO. 207. Hydrochloric Acid, extinguishes flame, is a powerful acid reddens litmus and also turmeric paper, may be liquified by a pressure of 40 atmospheres ; is very soluble in water) the solu- tion forming the common or liquid hydrochloric acid of the shops. 208. Two measures of HCl mixed with one measure of iVOg form t.hft Annn. pAo-in. nr 'WUrn-rniit.Sn+Jy* ^ t^iA <^* -t ?-*- IODINE. 67 sd through 7hen chlo- l added so CZO5 does 1 is a thick F. ; forms but which ith a com- m of oil of lined quite solid, very colorless md which t colorless moisture. 1 common erful acid, lified by a 'f the solu- Jid of the re of iV^O, sib'. SOD. Ohloritio unites with iVto form pcrchlorido of N or Oil of Azote NCl^, which is obtained by acting on a solution of sal- ammoniac by CI. Pcrchlorido of iV is a yellow oily fluid, insoluble in water, and most violently explosive and dangerous. LECTURE X. IODINE, BROMINE, FLUORINE. 210. Iodine, Symb. /; Bquiv. 12Y; Comb. Vol. (vapour) 1; Spec. Grav. 4-948 : Spec. Grav. of vapouc8-n6. Iodine was dis- covered by Oourtois of Paris In the year 1812; was named from ion "a violet" in allusion to its purple fumes; native sources are sea water, rough sea salt, various marine plants and animals, some mineral springs and certain rare lead and silver ores. / is obtained by heating tlio uncrystallizable residue of kelp (half vitrified ashes of sea weeds, prepared by the people of the Western Isles) with oxide of Mn and sulphuric acid. 211. Iodine is a bluish black semi-metallic looking, friable crystalline solid, easily volatile, fuses at 2250 and boils at 350o, forming violet colored vapour; is soluble in 7000 times its vol. of water, much more soluble in Alcohol or in solutions of the iodides of the alkaline metals ; is used in the arts for dying and also in medicine. Iodine communicates to the skin a fugi- tive yellow stain and exhales a strong odor like that of the sea beach. Phosphorus takes fire spontaneously in I. Iodine gives a blue color to a solution of starch, and, in fact, starch and / are mutual tests. I enters Into combination with metals and forms iodides. 212. / unites with /f to form Hydriodic Acid, m= 128, which is obtained by gently heating a mixture of 1 part phosphorus and 16 iodine stratified, in a small flask, with moistened sand. ^/ is a transparent colorless acid gas, very suffocating to the smell, and greatly resembling HCl. It has a spec. grav. of 4-385 ; is soluble in water ; condensiblo by pressure, and solidi- fiable by cold. 53 BROMINE. 213. / unites with O to form Iodic Acid and Periodic Acid. 214. Iodic Acid, 10^, is a white solid, obtained by the action of strong NOg on /. It is soluble in ether, alcohol and water, forming a strong sour solution, which is decomposed by heat. /O, forms iodates which much resemble the chlorates. 215. Periodic Acid, 10 ^, is a white solid hydrate, and is ob- tained by decomposing periodate of silver by water. It forms white crystals which fuse at 266" and are decomposed by a higher temperature ; lOj readily dissolves in water. 216. i unites with N to form Iodide of Nz= NI3 ; which is a black solid substance extremely explosive. 217. 1 also forms two compounds with Chlorine and one with Bromine. BROMINE. 218. Bromine, Symb. Br ; Equiv. 80 ; Comb. Vol. (vapour) 1 ; spec. grav. 2-966, of vap. 5-39. £r was discovered by M. Balard of Montpelier in the year 1826, and was named from Bromoa "fetor." It is found in sea water, mineral springs, mother liquor of kelp, native bromide of silver, &c. ; is obtained by action of chlorine on bittern and subsequent agitation with ether, which dissolves the Br and carries it to the surface. 219. Bromine is a deep red volatile liquid, solidifies at 40o, boils at 113«, giving off a red vapour. It is slightly soluble in water, more freely in alcohol^ and most abundantly in ether ; the aqueous solution bleaches ; Br bears a marked resemblance to CI and /; it supports the combustion of P and many metalsj and forms bromides which are analagous to the chlorides. 220. Br unites with Hio form Hydrobromic Acid HBr^ which is scarcely distinguishable from HCl^ and is obtained in a similar manner to Hydriodic Acid. 221. Br unites with O to form Bromic Acid, i?r O5, which exists only as an aqueous solution, and is obtained in the same man- ner as Chloric Acid. FLUORINE— StTLPHUR. 59 ic Acid. the action ,nd water, i by heat. [ind is ob- it forms y a higher yhich is a I one with FLUORINE. S22. Fluorine, Symb. f; Equiv. 19 ; was discovered by Davy, and named from its existence in Fluor-spar; it has not been isolated, i. e. is known only in combinations ; it bears a close analogy to CI, I and Br. 223. F unites with H to form Hydrofluoric Acid HF, which is obtained by action of oil of vitriol on Fluor-spar (Fluoride of Calcium) ; is a very volatile liquid, strongly acid and corrosive ; burns the skin like red hot iron, and produces a sore very diffi- cult to heal ; both the acid and its vapour rapidly decompose glass and corrode it, uniting with the silica, and are hence use* for etching on glass. apour) 1 ; ed by M. med from 1 springs, 3 obtained ition with face. es at 40<», soluble in Jther; the iblance to y metalsj es. Br, which 1 a similar lich exists ame man- LECTURE XI. SULPHUR. 224. Sulphur, Symb. S; Equiv. 16; Comb. Vol. (vapour) ^ ; Spec. Grav. 2-000 ; called also Brimstone (i. e. burnstone or burn- ing stone) ; exists nearly pure in volcanic regions as Sicily, India, South America, &c. ; is also found in combination with metals, as sulphides ; also as sulphuric acid in the sulphates, as gypsum ; also in organic matter. 225. Sulphur is obtained from the sulphides by heat, which vapourizes the S\ is obtained pure from common brimstone by sub- limation ; is a pale, yellow, brittle, tasteless, inodorous solid, fuses at 2260 and boils at eOO" giving oflF a deep brownish yellow vapour or gas, — up to SDO" it is liquid, at that point it becomes thick and viscid, is fluid again at or near the boiling point and on cooling goes through the same series of changes. If kept heated to between 500o and 600^ for some time and then poured in a thin stream into cold water it becomes a flexible viscid mass easily pressed into any shape and much used for taking casts of medals, &c. ; this form passes gradually into the brittle variety. 60 SULPHUR. IF if 220. Sulphur unites with the metals to form sulphides ; it unites with them in a manner similar to and CI] S is insoluble in water, but is soluble in alcohol, ether and oils; also in bisul- phide of carbon and chloride of sulphur ; is very combustible and burns at a very low temperature. 227. Brimstone is usually sold in rolls which are cast in a mourn-, Jlowers of sulphur ia obtained by vapourizing sulphur and condensing it in chambers; a third variety, lac-sulphuris, which is a precipitate of a white color, is prepared by treating persulphide of potassium with hydrochloric acid. COMPOUNDS OP SULPHUR AND OTvaBN. 228. Sulphur forms several compounds With the most im- portant being Sulphurous Acid and Sulphuric Acid. 229. Sulphurous Acid, SO^ ; spec. grav. 2'210 ; is formed when S is burned in the air or in or by treating sulphuric acid with mer- cury ; is a transparent gas, condensible by a pressure of two atmos- pheres and solidifiable by cold ; extinguishes flame, is irrespirable and has a suffocating odour. Water absorbs about 50 times its own vol. of SO^ forming liquid sulphurous acid or more properly a solution of sulphurous acid ; this, if exposed to the air absorbs Q and is converted into sulphuric acid. SO^ combines with bases to form sulphites. SO^ possesses considerable bleaching pro- perties and is used in the arts as a means of removing colors. 230. Sulphuric A jid, SO3, is the most important of all acids, and has been known since the 15th century ; is prepared in two modes. First, when green vitriol (green sulphate of iron) is dis- tilled a dark oily liquid, hence termed oil of vitriol, passes over ; this is, in reality, German or Nordhausen oil of vitriol, = HOfSO^ 4- ^Og— a very strong corrosive oily liquid, having a spec. grav. of 1-900. 231. The second method of manufacturing sulphuric acid de- pends upon the fact that when sulphurous acid, hyponitric acid and water are all present in certain proportions, the sulphurous acids becomes oxidized at the exnenae of thft livnonitH.^ at^m j_ . .. - _- — —^t -■>' •—^-— ss; it unites nsoluble in 30 in bisul- ustible and B cast in a Qg sulphur c-sulphuriSf by treating E> most im- rmed when i with mer- two atmos- rrespirable >0 times its re properly- air absorbs with bases ching pro- j colors. f all acids, red in two ■on) is dis- isses over ; vitriol, = having a LC acid de- nitric acid lulphurous >it.pir» nnirl SULPHUR. ei which, by the loss of one-half its O, sinks to the condition of binoxide of nitrogen. Thus : Hyponitric ( ^ ^ T^.-nn^;^^ of acid NO^^.S ^8 ^ ' Nz=NO^. 2 Equiv. of ( S , Sulphurous ) * Acid=2S0o } o: 2 Equiv. Of ) Z:^2(HO,5r03) Water.... ^ 2JJ0 = 2 Equiv. ofHydrated SO3. 232. Htdratdd Sulphuhic Acid, or common oil of vitriol, is a colorless oily liquid; spec. grav. 1-84, solidifying at 1 5" and boiling at 620O ; is an intensely acrid, powerful acid, which destroys orga- nic matter rapidly ; combines with bases to form sulphates ; dis- places almost all other acids in consequence of the strong affinity which it has for bases ; is used in the arts in the manufacture of soda, nitric acid, muriatic acid, chlorine, bleaching powder, sulphates, alum, &c. ; also in metallurgy. 233. SuLPHOiiio Acid combines with water in several propor- tions. Among the different hydrates, the following are the most important : — Hydrate of the Nordhausen Acid, HO, 2S0 Oil of Vitriol (spec. grav. 1-84), HO, SO^ ^cidof " « 1-78, H0,S03-\-H0 ^cidof « « 1.63, H0,S0.^ + 2H0 234. Anhydeous Sulphuric Acid, SO^, has recently ken ob- tained in the form of a white silky looking fibrous solid, having a powerful affinity for water, fusible at about 75°, readily vola- tile and having a density of about 1-97. 235. Chemists are very generally agreed that all the so called Oxygen acids aro in reality Hydrogen acids. No well marked acid exists^in which Hia not present and all the sulphur acids pos- sess the same aeutraiizing power though the quantity of O they 62 flULPHtlR. w hi contain ia so differont. H is therefore to be considered as the " acidifying principle," and an acid may be defined to be " a compound of hydros: en with a simple or compound radical iti which the H may be replaced by any other metal." 236. Tlio following are the compounds of S and according to the old and new systems. Acids. Sulphurous Acid,.... Sulphuric Acid, Hyposulphurous Acid., Hyposulphuric Acid, . . Trithionic Acid, Tetrathionic Acid, .... Pentathionic Acid, . . . Old View. Now View. Equivalents where H unitoa with the comifound radicals 803,^03+0, Ac. HO,SOt H0,S03 HO,SiOi HO,S,0, HO,S,0, H,SO, H,S,0, ^•+(503+0). H+(S03+503). H+(SO,-\-SO,+S). COMPOUNDS OF SULPHUR AND HYDROGEN. 237. SuLPHUBBTTBD Htdboqbn, Symb. HS, is spontaneously generated by the decomposition of organic substances contain- ing sulphur; is prepared by acting on the protosulphide of iron by hydrochloric or dilute sulphuric acid ; is a color- less transparent gas, having a very offensive and peculiar smell like that of putrid eggs ; is condensible under a pressure of 17 atmospheres and is solidifiable by cold ; it may be collected over water, which however gradually absorbs it. HS is highly poison- ous, and often causes death ; small birds die very soon in gas containing rho of this gas ; g^^^ Isilled a dog ; and ihs a borse. It has a spec. grav. of 1-1 Y86 ; it extinguishes flame but burns itself with a pale flame forming water and SO2. Water absorbs two or three times its vol. of HS, at all important. PHOSPUORtJS. 63 red as the to be " a %l in which according ks whore H A^ith the 1 radicals + O. Ac. -0). ■S). ■SO,). -SO,+S). ■SO,+S,) ■SO^)-{-S, itaneously 3 contain- alphide of I a color- iliar smell sure of IT ected over ily poison- on in gas Tj a horse, but burns 3r absorbs 230. Sulphur forms two compounds with Chlorine, viz. : Sub- chloride of 5 = S,Cl, and Chloride of ^ = SCI, and it also forms analogous compounds with / and Br. 240. With Carbon, sulphur forms Bisulphide of Carbon, C5„ which is obtained by passing tiie vapour of sulphur over ignited charcoal and condensing the result by cold. CS^ is a transparent colorless liquid, insoluble in water, possesses a strong and disagreable fetid odor; spec. grav. 1-272 ; boils at 11 S"; is very volatile; dissolves sulphur, phosphorus, most oils, resins, &c., exists often in coal gas, from whicli it cannot be separated by lime like the other sulphur compouuas. 241. Sulphur and N form tersulphido of c'*rf>iTen = iV5;,. LECTURE XII. PHOSPHORUS. 242. Phosphorus, Symb.P; Equiv.32; Spec. Grav. 1-77, was discovered by Brandt of Hamburg in 1669, and named from phos, " light," and pherein " to bear" ; is obtained from boa j-earth, or native phosphate of lime, which is decomposed by dilute sul- phuric acid and the phosphoric acid mixed with i its weight of powdered charcoal and distilled. The P is thus deoxidized and is collected in water. Great precaution ia necessary in the dis- tillation. 243. Phosphorus is a wax-like, nearly transparent, brittle, yet flexible substance, fusing at llQo and boiling at 572o; very com- bustible ; exhales fumes in atmospheric air, which are luminous in the dark ; is insoluble in water, but is soluble in alcohol, ether, oils, bisulphide of carbon and chloride of phosphorus, and from the latter liquids it is often deposited in octahedral and dode- cahedral crystals ; is very poisonous, but is nevertheless used cautiously in medicine ; unites with the metals, &c., to form phosphides ; is used chiefly in the manufacture of matches ; requires to be kept under the surface of water; takes fire spon- taneously in CI and in the vapour of / or Br. 64 PHOSPHORUS. 244. Amorphous P, i.e., phosphorus in an allotropic state, was discovered by Schrdtter, and may be made by exposing common P for 50 hours to a temperature of about 4T0o F. in an atmosphere unable to act chemically upon it. It is a reddish-brown looking solid ; insoluble in bisulphide of carbon, terchloride of P, or naphtha ; does not take fire in air till heated to 500° ; has a spec. grav. of 1-964; when heated {.bove 500o it is reconverted into common phosphorus. COMPOUNDS OF PHOSPHORUS AND OXYGEN. 245. P forms four compounds with O, viz : Oxide of P=P2 ; Hypophosphorous Acid = PO] Phosphorous Acid zzPOg ; Phos- phoric Acid = PO^. 246. Oxide op Phosphorus, P^O, produced when P is placed in boiling water pnd a stream of cast upon it, is an inso- luble red powder which burns at about 600". 247. Hypophosphorous Acid, PO, is very little known ; it is formed when phosphide of barium is put into hot water ; is a thick sour liquid ; forms with bases hypophosphites, which are all soluble in water. Hypophosphorous Acid has a great aflBnity for O, and is therefore a powerful deoxidizing agent. 248. PHoaPHOBous AciD,P03, is formed when P is burnt in rari- fied air, or by acting on terchloride of P by water ; the acid crys- tallizes with 3 equiv. of water or becomes SHOfPO^ ; is a power- ful deoxidizing agent ; unites with bases to form phosphites. 249. Phosphoric Acid, POg, is formed when P is burnt in O or in free air, or is obtained by decomposing phosphate of lime by sulphuric acid ; in the anhydrous state it is a white uncrystallizable solid, fusible at a red heat and is then transpa- rent I it is very deliquescent and rapidly attracts moisture from the air ; is very soluble in water ; strongly acid ; reddens vege- table blues and unites to bases to form phosphates. 250. Phosphoric A "d forms three distinct hydrates which unite with bases forming distinct classes of phosphates. If we view them as compouivis of aubyUrous acid and water, then they are PO^HO; P0^,2H0 j PO,,dHO. If on the other hand we view PHOSPHORUS. 65 ic state, was g common P atmosphere 3wn looking de of P, or 500<»; has a reconverted of P=P2 0; PO3 ; Phos- P is placed , is an inso- :nown ; it is water; is a frhich are all it aflBnity for )urnt in rari- le acid crys- is a power- [)sphites. P is burnt J phosphate it is a white len transpa- Disture from ddens vegc- rates which ites. If we r, then they and we view them as hydrogen acids, then they are quite distinct compounds, and their formulas will be: PO,H; PO„H, ; PO„H,. Thei^ names are as follows : :c , e, 3 ^:ll Protohydrated, Glacial, Metaphosphoric or Monobasic Phos- phoric Acid, POs,HO, or POe,H. PO^fmt^PO ^^'°P^°'P^°'^° ""' ^^^^^^° Phosphoric Acid, Terhydrated, Common or Tribasic Phosphoric Acid PO,,ZHO or POgfSH, When Common or Tribasic PO, is heated for a long time to 4170 It loses 1 equiv, of water and becomes P0„2^0 or BibaL.c and this heated to redness gives off another equiv. of water and becomes PO„HO or Monobasic Acid. 251. The Monobasic Acid forms salts containing 1 equiv. of base to 1 of acid ; the Bibasic Acid forms salts contain ag 2 equiv. of base to 1 of acid ; and the Tribasic Acid forms salts containing 3 equiv. of base to 1 of acid. COMPOUNDS OP PHOSPHORUS AND HYDROOBN. 252. Phosphurbttbd Hydroobn, Symb.P^3. This may be obteined by heating in a small retort hydrated phosphorous acid Which IS, by such treatment, decomposed into phosphuretted hydrogen and hydrated phosphoric acid. Thus obtained, PH, has a spec. grav. of 1-24; possesses a highly disagreeable odor burn?w^? *\^t of garlics; is slightly soluble if water, and J^^' f^' T/ ^^'° ^' °^*^^"'^ ^y ^oi"°« together in a retort of small dimensions caustic potassa or hydrate of lime, water and phosphorus. Water \ ^^*^''°^®°- ^^^:^Phosphurotted Hydrogen. ( Oxygen^ Phosphorus Phosphorus Lime Hypophosphite of Lime. 66 PHOSPHORUS. S) i 264. Pifa formed by the latter method is spontaneously inflam- mable when admitted into the air or into 0. PH^ exists in both a spontaneously inflammable state and a state not spontaneously inflammable. It ia said that the first may be changed into the second by a small quantity of vapor of ether, oil of turpentine, &c., and the second into the first by the addition of a minute quantity of nitrous acid. 255. In reality there exist three compounds of P and H, viz :— 1st. A fluid, P^HiQ ; 2nd. a solid, P^H] and 3rd. the gas, PH3. In the above process the fluid is first formed and is spontaneously resolved into the other two, thus Ps-^io = PzH+ZPH^. The gas PH-i acquures its spontaneous combustibility by dissolving some of the liquid F^^io This liquid renders any other com- bustible gas spontaneously inflammable. 256. PH3 when kept for some time loses the property of being spontaneously inCammable and the solid phosphide of hydrogen PgHis deposited on the inside of the containing jar or bottle. 257. P unites with chlorine by taking fire spontaneously in it, thus forming two compounds, PCl^ and PCl^. 258. Terchloride of Phosphorus, PCI3, is formed when dry CI acts on excess of P -, it is a transparent, colorless liquid, specific gravity 1-450, boils at 173<»; fumes in the air and has a suflPbcating odour; is rapidly decomposed by water— HCT and POajSHO being produced. 259. Pentachloride of P=zPCls, is formed when CZ in excess acts on P. The latter burns and produces a white solid ; vola- tile at 200° ; fumes in the air ; is decomposed by water and resolved into HCl and PO^jBHO. 260. P and iV^form a compound PN^. 261. P forms compounds with / and Br, which are analogous to those it forms with (^l. 262. When P and S are heated together under water, they combine and form several compounds which are exceedingly in- flammable and have a strong tendency to explode vioieuUj^ wLeu heated. SILICON. 67 ly inflam- es in both taneously . into the irpentine, a minute £r,viz: — gas.PHg. taneously H3. The iissolving ther com- Y of being hydrogen : bottle. )usly in it, lien dry CI id, specific luffbcating P03,3HO I in excess (lid; vola- ivater and analogous (rater, they jdingly in- sutiy when LECTURE XIII. SILICON. 263. Silicon, Symb. Si; Equiv. 21-3; was discovered by Berzelius in 1824 and named from its being the chief constituent of silex or flint. Si is prepared by igniting the silico-fluoride of potassium with potassium, water dissolves off the fluoride of potassium and leaves the Si as a nut-brown powder. Si is infusible ; has neither taste nor smell ; burns in the air or in O when strongly heated, and forms silica ; Si exists in an allo- tropic form which is not combustible. 264. Si unites with O to form Silicic Acid or Silica, SiOs. This is one of the most abundant substances in nature ; exists pure in rock crystal, flint, quartz, agate, jasper, heliotrope, cornelian (the three latter color :d by oxide of Fe) ; amethyst (colored by oxide of Mn) ; opal and calcedony (with water). Many sands a:id sandstones are nearly pure Silica or Silicic Acid. 265. SiOa is obtained pure by decomposing an alkaline silicate by means of hydrochloric acid and washing and drying the pre- cipitate ; is a snow-white powder ; is insoluble in water and all acids except hydrofluoric acid ; fusible at a white heat and may be drawn into threads ; spec. grav. 2-600 ; with alkalies and alkaline earths it forms silicates, all of which, except those con- taining an excess of the stronger alkalies, are insoluble in water. The greater number of rocks and minerals consist of silicates, especially those of alumina, lime, magnesia, oxide of iron, potash, and soda. The silicates of potash and soda, when heated to redness, form glass, which is insoluble in water if the acid is in excess but very soluble if the alkali predominates. SiOg enters largely into the composition of many vegetables and to some extent to that of all— also in animals. 266. Silicon and F unite to form Pluosilicic Acid Gas SiF^. It may be formed by a mixture of fluoride of calcium, silica and oil of vitriol ; is a transparent, colorless gas, which may be 68 SELENIUM— BORON. collected over mercury ; spec. grav. 3'600 ; fumes in the air, is strongly acid, and is instantly decomposed by water, being resolved into hydrofluoric acid, gelatinous silica, and hydro- fluosilicic acid. LECTURE XIV. SELENIUM. 267. Selenium, Symbol Se ; Equiv. 40 ; was discovered by Berzelins in the year 1818, and was named from selene, " the moon." Selenium is a reddish brown solid body, with a semi- metallic lustre, and having a spec. grav. of about 4*300. It melts at 482°, and boils at 1292" ; is insoluble in water, and exhales, when heated in the air, a peculiar odour resembling that of horse-radish. It forms with O two acids, viz., Sblbnious Acid, SeOz, and Sblbnio Acid, SeO^. It also unites with H, Sj P, C/, Br and /. W^ih H it forms Hydroselenic Acid or Selenu- retted Hydrogen, a deadly poisonous gas which inflames the eyes, and for some hours destroys the sense of smell. In all its chemical relations Selenium bears a very strong and remarkable resemblance to Sulphur. BORON. 268. Boron, Symbol B ; Equiv. 11 ; was discovered simul, taneously by Davy, Gay Lussac, and Th^nard, and was named from its being the peculiar principle in Borax (Arabic buruk) which is a biborate of soda. 269. Boron exists native inboracic acid, and is obtained from anhydrous boracic acid by ignition with potassium, which de- composes the acid, abstracting the O. Thus obtained, it is an amorphous brownish olive-green powder, having neither taste nor smell. It is insoluble in water ; has a spec. grav. of 2-000 ; and when heated in air or in O it burns, forming boracic acid. Boron Las also lately been ubtained in two crysialliue furmu, bearing a close resemblance to diamond and graphite. THE METALS. 69 I tbo air, is Iter, being tnd hydro- covered by •:?'ii they diflfer very widely. Potassium and Sodium are so sou, that they may be kneaded by the fingers ; Lead, Silver, and Tin may be cut with a knife ; Iron, Nickel, and Antimony, are much harder, and Iridium is one of the hard- est of known bodies. 278. Mallbabiutt and Djiotility.— Some metals, as Anti mony. Bismuth and Cobalt, are brittle, i. e., if hammcittd thcj' break to powder ; others, as Tin, Copper, Silver, Platinum, Pal- ladium and Gold, may be hammered out into very thin sheets (51 sq. inches cf the finest gold leaf weigh oaly 1 grahi). The most ductile metals are Copper, Palladium, Iron, Silver, GcM, an*^ Platinum (a single grain of Gold may be diawn out Into a ^ ire of 550 feet in length, it?/^ a. grain of Platinum, which is pixt xves more ductile, may ha irawa into a wire of 3,300 feet in leagtb). 279. Thnjcity. — The teaiC'ly of metals is determined by comparing the weight vt /.h wires of equal diameters, bi^tof diflfereut metals, wMi snsidn. It has been ascertained that wires having a diameter of about -^^e of an inch, have a tenacity as follows : — Iron wire supports 550 lbs. Copper " 303 " Platinum " 274 " Silver « 187 " Gold wire supports 150 lbs. Zinc " 110 " Tin " 35 " Lead « 28 « 280. iusiBiLiTY.— Mercury is liquid at all temperatures be- tween -390, and+660«>, Potassium fuses at 150«, Sodium at 194», Tic at 442, Lead at 612o*>, Copper at 1996o, Gold at 2016°, Iron, at 2786**, while Platinum and some others require the intense heat of the oxy-bydrogen blowpipe to melt them. 281. V0LATII.ITY — The metals, in general, are highly fixed bodies, but it is probable that all of them may be volatilized at the highest temperatures. Mercury is slowly dissipated in vapour at all temperature above CS", and boils at eeo®. Mercury, Cad- mium, Arsenic, Tellurium, Zinc, Potassium, and Sodi'im, ate all converted into vapours at a temperature varying from a lew to a briffht red heat, and are occasionally distilled, from thf '»- cility with which they are vc./stTli«ed. tassium And the fingers; Iron, Nickel, of the hard- lis, as Anti nmeied thtj' atinuao, Pal- in sheets (5t . The most r, GcM, am' L Into a wire 1 is fix t rjies t in leagtb). bermined by Bters, bi:?tof )d that wires i tenacity as s 150 lbs. 110 " 35 " 28 « eratures be- iumat ISi**, 2016*', Iron, the intense highly fixed olatilized at ed in vapour ercury, Cad- Sodi'im, are r jfrom a Uxf from the **'- THE METALS. ^i CLASSIFICATION OF THE MKTAL8. 282. The metals have been separated into eight classes, which are distinguished from one another, chiefly by the facility with '^hica they decompose water, and the effect of heat in reducinir their rvides. * CLASS I.— MBTALS OF THB ALKALIES PROPBB. These metals decompose water even at 32o, with hissinir effervescence, and usually with flame ; they are rapidly oxidized on exposure to the air ; their oxides are powerful bases, and are vfiry soluble and very caustic. They are : Potassium, Sodium, Lithium, Ammonium ? CLASS II.— MBTALS OF THK ALKALINB EARTHS. These have also a very strong affinity for oxygen, and, except magnesium, they decompose water at ordinary temperatures, but without flame. Their oxides are powerful bases, but are less soluble, and less caustic than those of class 1. They are : Barium, Strontium, Calcium, Magnesium. CLASS III.— MKTALS OF^ THB BAUTHS PROPBB. These metals do not decompose water at ordinary tempera- tures, but do so much below a red heat. They burn in the ain when heated and form oxides which are less powerful bases than those of classes I and II, and which being earthy in aspect, and quite insoluble, are called earths. They are : Aluminum, Yttrium, Zirconium, Giucinum, Thorium, Erbium, Terbium, CLASS IV.-MBTALS PROPBB, OF WHICH THB PROTOXIDBS ABB ISOMOBPHOUS WITH MA0NB8IA. These do not decompose water except at a red heat, or at ordinary temperatures in the presence of strong acids. They Iron, Nickel, Cobalt. zinc uaamium, Lead, Manganese, Copper. 12 THE METALS. CLASS V. — OTHBR UITALS PBOPIB HAVING IBOMORPHOUB BELATION0 WITH TH> MAONBBIAN VAHILT. These do not decompose water at any temperature, nor in the presence of the strong acids. They do, however, at a red heat decompose the vapour of water with considerable effervescence, They are : Tin, Chromium, Vanadium, Tellurium. Tungsten, Molybdenum, Titanium. CLASS VI. — ^MITALS ISOMORPHOUB WITH PHOSPHOBUB. These even at a bright red heat decompose water very feebly, but their oxides, once formed, cannot be reduced to the metallic state by heat alone. They are : ArseniCj Antimony, Bismuth. OLABB VII. — THE NOBLE IfBTALS. these do not decompose water under any circumstances, their affinity for Oxygen is so feeble that they do not rust or tarnish on continued exposure to the air^ and their oxides are reduced by a high temperature. They are : Silver^ Mercury, Gold, Palladium^ Platinum, 'Osmium, Iridium. Rhodium. Ruthenium. CLASS VIII. — METALS I»B0PBB NOT INCLUDED IK THE FOBEClOINa CLASSES AND WHOSE OXIDES ABB NOT REDUOIBLB BT HEAT ALONE. Uranium, Lanthanum, Tantalumj Niobium. Cerium^ Didymium^ Ilmeniumj Pelopium. NoTB.— The remaining metals Aridium, Donarium, and Norium, are not suffioientljr known to enable us to determine in what class they flail. 8 BELATION0 B, nor in the t a red heat fervescence, 'ellurium. OBUS. very feebly, the metallic th. tances, their t or tarnish Eire redaced mm. FORIC^OINO B BT HBAT fiobium. elopium. rium, are not Ley fall. METALLIC OXIDES. 73 LECTURE XVI. COMPOUNDS OP METALS WITH METALLOIDS AND WITH OTHER METALS. METALLIC OXIDES. 288. Metala combinod with oxygen form three classes of oxides, which with their general formulas are as follows :— Name. Suboxide, Protoxide, Sesquioxide, I. BASIC METALLIC OXIDES. Examples. General Formula. MO Cu^O CuO, FeO, HgO, VO, jSgO Fe^O^, Co^O.^^ AfngOg, ^ugO-^, Os^O^ II. — NEUTRAL METALLIC OXIDES. Binoxide, MO M,0, Ph^O^, JMH3O4, ^6304 PbO^, BiOi, MnO^, PtO^, rOi in. — ACID METALLIC OXIDES. Binoxidfi, Teroxide, Quadroxide, Pentoxide, MOg MO^ M^Oj MO^ MO, Titanic Acid TSOj, Stannic Acid SnO^ Chromic Acid CrO^^ Ferric Acid, JfeO,, Arsenious Acid, AsO^^ Permanganic Acid JlfngO^ Osmic Acid OsO^ Arsenic Acid.4«08 ; Antimonio Acid Sh 0, REDUCTION OF THE METALLIC OXIDES. 284. The metallic oxides are deprived of their oxygen and are thus reduced to the metallic state by diflterent methods. I. The oxides of the noble metals, or those in Class VII., are reduced by a red heat alone. II. Many oxides, as, for example, those of Copper, Iron, Tin, Potassium, Barium, &c., are reduced by the joint action ilu 74 METALLIO CHLOBIBIIS AND SULPHIDES. NoTK.— A deoxidising agent is a body whose affinity for oxygen is so ■trong that it witlidraws it, under certain circumstance, from tlie oxide* Carbon, Hydrogen, Carbonic oxide, &c., are deoxidising agutits, but the most powerful are the forraiates and cyanide of potassium. The mode in whioh the simple reducing agents aud IT act is as follov. s :— 3fO + C- iHf + CO a. .! if + HO III. The oxides of sever* ruetai» Ct.n be reduced ouly by means of a powerful ^'alvanio battery. When reduced by this mode the metal always appears at the negative pole of the battery. IV. Certain oxides in solution are precipr lied iu tlie jiet»»''io state by other metals which have a stronger adinity for the oxygen. Thus, copper precipitates silver, and iron precipitates iopper. METALLIC CHLORIDES. 286. The metallic chlorides are also reduced by several methods, as by heat alone ; by the action of another metal for •which the chlorine has a greater affinity; by the action of hydrogen ; by boiling with a formiate, &c. MET;iLLIC SULPHIDES. 286. The metallic sulphides are reduced— I. By roasting them in the air, by which means the sulpiiur is converted into sulphurous acid and the motal into oaide, which latter is r»r!uced by being ^ain hea fed with charcoal. TT . By heating to redness in an atm.osphere of hydrogen. Thus, ins + fl = iif + ha 01- jtfgSa + i, = itfg -}■ ms III. By roasting with another metal. Thus, HgS^ + Fgg = fljgr + 2 FeS IV. By heating with cyanide of potassi o ith one of th formiates. Thus, tersulphide of set roasted wit^ for'^rlate of soda. 16. ALLOTS. » oxygen » w >m the oxide* unta, but the The mode in ed ouly by en reduced lie negative liie jietft'^io affinity for ir, and iron by several er metal for action of the suipiiur I motal into . heated witb ydrogen. ih one of th oasted wit^ ALLOYS. 287. The compounds of motels with metels re called alloys, except when mercury is present, vuen they are termed amal- gams. The principal alloys are the following :•— FiNi SoLDiB = 2 parts tin + 1 part lead. It melts at 360«. GoABSB SoLDiR = 1 part tin + 3 parts lead. It melts at SOO*. Piw R = tin + small quantities of antimony, copper, and bismuth. The inferior kinds contain more or less lead. Nbwton's Fubiblb Mbtal = 8 parts bismuth 4- 6 parts lead + 3 parts tin. It melts below 212«. Robb's FrjgiBLB Mbtal =: 2 parts bismuth + 1 part lead + 1 part tin. It melts at 200o. FusiBLB Mbtal = 248 parts bismuth + 156 parts lead + 90 parts tin +13 parts mercury. This composition melts at 162». Typb Mbtal i= 3 parts lead + 1 part ai atony + a small quantity of tin. Bbonzb =: 90 parts ccper 4* 10 parts tin. Bbll Mbtal and Qono Mbtal = 80 parts copper + 20 parts tin. Spbculdm Mbtal = 2 parts copper + 1 part tin + a little arsenic. Bbass = 4 jarts i -f 1 part zinc. When the proportion ( -ic is increase'^ ^ ja tombac, Dutch gold, and pinchbeck. Gbrhan Silt - 100 parts copper + 60 parts zinc + 40 parts nickel. The ' terior ^ Is ar deficient in nickel. Tin Amalgam = tin ercury , is used for silyering the backs of mirrors. Elbctric Am .qam = 2 parts zinc + 1 part tin + 6 parts mercury. SALT radical THBORT. 288. A salt ha«i been defined to be "a co; ipound of an acid with a base, and according to this definition tJ e compounds of CMorine, Iodine, Bromine, and Fluorine, with the metels, are salte. Since, howt s^er, these bodies pos "ss ^.i a very high degree the saline characters, as turmerly thought necessary to separate sali;^ Into two distinct classes ^ I 76 BALT-BADIOAL THXORT. l8t. Oxy-saltt, or those which oonsist of oxjgen-aoida com- bined with baaei . and. Haloid taltt, or thoie which eonsitt of a metal united to a salt-radical after the type of oonunon salt (Hals « sea- salt," eidos " form.") 289. We have seen that a radical is any body simple or com- pound which is capable of chemically uniting with an elemen- tary body. A $alt radical may b. defined to be a body (either simple like chlorine or compound like cyanogen) which forma an acid with hydrogen and a $alt with aodium or any other metal. 200. The salt-radical theory assumes that all salts are binary compounds, being proauced by the union of a metal with a simple or compound salt-radical. 201. The following exhibits the changes in nomenclature and notation that the adoption of this theory would render neces* pary. ON THE ACID THBORT. Hydrated sulphuric acid, sulphate of oxide of hydrogen or hydric sulphate, HO 4- 80^ Sulphate of potash, sulphate of oxide of potassium or potash sulphate, KO -|- SO^ Hydrated nitric acid, nitrate of oxide of hydrogen or hydric nitrate, H0+ NOg Nitrate of potash, nitrate of oxide of potassium or potash nitrate, - KO + NO Chloride of hydrogen or hydrochloric acid, H-\r CI Ghloride of potassium, K-^ CI Cyanide of hydrogen or hydrocyanic acid, H -\- C^N Cyanide of potassium, K-\- C^N ON 7HB BALT-BADIOAL THBORT. Sulpbionide of hydrogen or hydrosulphuric acid,. H-\- SO^ Sulphionide of potassium, JT + 80^ Nitrationide of hydrogen or hydronitranic acid,. . H + NOg Nitrationide of "Qt^Bsium ^^^^^^^^^^^fs^^^^^s^^ K -^ NQ= -acids com- ftl united to {Hals "sea- pie or com- an elemen- ody (either 'hich forms ither metal. i are binary ital with a olature and ider neces- ydrogen or HO + SO3 K0+ SO3 HO+NOs W-{.NO H^Cl K-\- CI H-\- C^N K-ir CtN H+SO^, K+ 80^ H-\-NOs VJ-fiH- POTASSIim. Tt Chloride of hydrogen or hydrochloric acid H-^- CI Ohloride of potassinm, K-i- CI Cyanide of hydrogen or hydrocyanic acid, H+ C^N Cyanide of potassium, K-{- C N 292. The advantages of the salt-radical theory are the fol- lowing : — I. It makes but one class of salts instead of two classes. II. It affords a more simple and philosophical explanation of the action of certain metals upon acid solutions. III. It accounts for the remarkable law that to produce neu- tral salts " Bases always combine with as many atoms of acid as they themselves contain of oxygen," i. e., a pro- toxide forms a neutral salt with one atom of an oxygen- acid, a sesquioxide, with three atoms of an oxygen-acid ; a binoxide, with two atoms of an oxygen-acid, &c. Thus, the neutral sulphates of a metal are constituted as fol- lows :— Old Vikw. New Virw. M^O+SO., Jlfg+SO^ = Subsulphionide. ^0+SO, M+SO^ = Protosulphionide. M^O^+SSO^ Mt-{-3S0^=z Sesquisulpbionide. MO^+280, M+2S0^ = BisulpLionide. These sulphionides correspond to the known chlorides MaCl MCI, MtCl,, &nd MCl^. ' * ' NoTB.-^ere are, however, certain strong objections to the salt-radical theory, which must, until they are removed, prevent its general adoption. METALS OF THE ALKALIES PROPER. LECTURE XVII. POTASSIUM. 298. Potassium (Kalium), Symb. K; Equiv. 9; Spec. Grar. 0-865 ; was discovered in the year 180T, by Sir H. Davy, as a •_■•_•«»»•. i*v«t of potusb which is o$ide of potassium. T8 POTASSIUM. 11 . Potassium is a bluish white metal, so very oxidizable thht it can be preserved only in fluids or gases containing no oxygen ; is commonly preserved in the hydrocarbon, mineral naphtha.— Potassium is brittle and crystalline at 32^ ; is soft like wax at ordinary temperatures ; melts at 160^, and boils at a red heat, forming a green vapour. When melted under the surface of naphtha, potassium exhibits a high degeee of metallic lustre, but it tarnishes instantly on exposure to the air. When heated to dull redness in the air, or when thrown upon the sur* ' face of water, it takes fire, burns with a beautiful violet colored flame, and is converted into potassa, or the oxide of potassium. Potassium is distinguished above all other bodies by its intense affinity for oxygen. Potassium is the characteristic alkali of the Vegetable Kingdom as sodium is of the Animal Kingdom. It exists as a constituent of most rocks (feldspar contains 12 per cent.), is obtained as potash by lixiviating the ashes of plants. Metallic potassium is obtained from the carbonate of potash, by decomposing it by the joint action of heat and charcoal. 294. The principal compounds of potassium are : Protoxide of potassium, KO. Peroxide of " KO^. Chloride of " Ka. Iodide of " KI. Bromide of " KBr. Protosulphide of potassium KS. Pentasulphide of " KS^ Ferrocyanide of " KtFeCyv^mO Ferridoyanide of " K»Fe»Cyt Cyanide of " K Cy. 296. Pbotoxidb of Potassium, Potash, or Potassa, Symb. KO = 47 ; is a white powder which rapidly absorbs water from the air, and becomes common or cautic potash, whiuh is KOj HO. Caustic potash is obtained by decomposing the carbon- ate of potash by lime. It is a semi-crystalline solid ; has a specific gravity of 1*700 ; is fusible at 700** ; is very deliquescent; is soluble in water and in alcohol ; its solution {aqua potassa) is caustic, and highly alkaline. Caustic potash is much used in medicine as a cauterizer. 296. loDiDB OF Potassium, JKT/, is obtained by dissolving iodine in a solution of potassa until the mixture is neutral. This mixture, consisting in part of Kl, and in part of KOJOa, is evaporated POTASSIUM. 79 sable thttt it no oxygen ; naphtha.— like wax at a red heat, B surface of lUic lustre, lir. When >on the sur* 3let colored potassium. ' its intense Ikaliofthe agdom. It ains 12 per 3 of plants, potash, by :oal. s. s» iFeCyt+iHO tFeiCy* 3SA, Symb. water from whiuh is nhe carbon- is a specific descent; is potassa) is ich used in tring iodine lis mixture, evaporated to dryness, and then heated to redness in order to decompose the KO,IO^. Iodide of potassium crystallizes in cubes or prisms which are white and opaque. It has an alkaline reaction owing to the presence of a small quantity of KO,COf ; is soluble in water, and to a less degree in alcohol ; is not poison- ous even in doses of several drachms ; is much used in medicine, and its solution is employed as a solvent for iodine--30 grains of KO and 20 grains of iodine being usually dissolved in one ounce of water. The solution of bromide also dissolves bromine but that of chloride has no affinity for chlorine. Both the iodide and bromide are extensively employed in photography. Oh loride of potassium has a taste like that of common salt, which it also resembles in most other respects. It is principally consumed in the manufacture of alum. 297. Pebrooyanidb of Potassium or yellow-prussiate of potassa is produced by exposing carbonate of potash mixed with dry blood, horns, clippings of hoofs or hides, or other animal matters, to a red heat in an iron pot. It is a lemon-yellow colored salt crystallized in quadrangular tables with truncated angles and edges ; soluble in 4 parts of cold and in 2 parts boiling water j insoluble in alcohol, has a saline taste and is not poisonous. 298. Fbrridcyanidb of Potassium or red prussiate of potassa symb. K^Fe^Cy^ or 3^+2(i'eC^3) is obtained by treating a solution of ferrocyanide of potassium with chlorine gas until it ceases to give a precipitate of prusslan blue with a persalt of iron. The mixture contains chloride and ferridcyanide and the latter is separated by crystallization. Ferridcyanide of potas- sium is a transparent red salt, crystallized in anhydrous rhombic prisms ; soluble in about 4 parts of cold water ; is, in solution, a delicate test for iron which it throws down as prussian blue. < 296. Cyanidb of Potassium, KCy, is obtained with difficulty from ferrocyanide of potassium. It is a colorless salt crystallized in cubes ; in contact with air becomes cyanate of potassa ; is similar in its action on the animal economy to hydrocyanic acid and is often employed as a source of hydrocyanic acid of known strength ; thus, 24 grains pure cyanide of potassium, 56 grains !■!•:' 80 POTASSIUM. of tartaric acid and one ounce of water agitated together in a stout phial cloaed by a cork and afterwards filtered gives a solution of iO grains of hydrocyanic acid in 1 ounce of water or rather more than 2 per cent. 300. Thb Sulphides op Potassium are KS, KS^, K83 and KSg and an impure sulphide called H^ar Sulphuris or liver of sulphur. This last is sometimes employed in medicine and is prepared by fusing a sulphur with carbonate of potassa. Its composition of course varies with the proportion in which the ingredients are employed, but it is always a mixture of one or more of the above sulphides with hyposulphite and sulphate of potassa. 301. The principal salts of potash are the following : Nitrate of potash, KOyNOs. Carbonate c/ potash, KO,COi. Bicarbonat':tof" BOjCO%-\-KO,CO% Sulphate of potash, KO,SOz. Chlorate of potash, K0,C105. Acetate of potash,...JrO,C4Jy3 03. Oxalate of pota8h„..JrO,C203+J3'0, Tartrate of potash, iKO.CsS^Oi 0, Urate of pot, K0^O,C\ J2 gi^* O4 , Cyanate of potash, KO,CyO. 302. Nitrate op Potash KO^NO^^ is called also Nitre or Salt- petre. It is a white crystalline solid, having a specific gravity of 1*933 ; is very soluble in water, and net at all soluble in absolutd alcohol ; is used as a source of nitric acid, as a manure, and also for curing meat, owing to its antiseptic properties. It is likewise employed in the manufacture of gunpowder, which is very nearly C3 SNit. COMPOSITION OP GUNPOWDER. Theoretical Mixture. English. French. Sulphur 11-9 12-5 ^ . . 11-5 Charcoal 13-5 12-5 13-5 Nitre 74-6 75-0 75-0 100-0 1000 100-0 When gunpowder is fired, the results are carbonic acid, nitro gen, and sulphide of potassium. Thus :— ^ether ;n a )d gives a e of water '3 and KSg ir liver of ine and is tassa. Its which the J of one or mlphate of CiOz-\-no. KCsHiOio, loEaNAOA, CyO, ;re or Salt- So gravity soluble in a manure, )erties. It ier, which SODIUM. DBFLAORATION OF GUKPOWDflB. 3 Carbon ^- Nitrate of Potash.. - 81 Sulphur g. In the explosion of gunpowder the nitre is decomposed by the charcoal, the sulphur merely accelerating the process of de- flagration, and supplying heat. One cubic inch of good powder yields about 800 cubic inches of cold gas, and as at the moment of explosion the gas is red hot, we may safely reckon the ex- pansion as about 1 into 2000. Gunpowder may be analyzed by 1st. Boiling in waitr to remove the nitre ; and 2nd. Exposing the residue to a tolerably strong heat to vapourize the sulphur. Note.— It is essential to the propelling force of gunpowder that its explosion, though occupying only an exceedingly short space of time, should not be absolutely instantaneous. Fulminating mercury and other explosive compounds that burn more rapidly than gunpowder are not adapted to the propulsion of projectiles, since if substituted for powder, they shatter the gun, but do not project the ball. 303. CabSonatk of Potash in an impure state, forms the potashes and pearlashes of commerce. It is a white, fusible, highly alkaline solid, which crystallizes with 2 equiv. of water. It is very soluble in water, and its solution feels greasy to the touch. ench. 1-5 3-5 5-0 0-0 >cid, nitro LECTURE XVIII. SODIUM. 304. Sodium (Natrium) Symb. Na-, Equiv. 23; Spec. Grav. 0-934 ; was discovered by Davy, in the year 1808, in soda, which is the protoxide of the metal. Sodium is, with the exception of aluminum and perhaps potassium, the most abundant metal on the globe ; it constitutes two-fifths, by weight, of salt, and existe as an oxide in nianv tnjno|ia]a^ 'SI -1 -t- 82 ISODIU^. i 1 ii ' ,t 111 Sodium is obtained in a metallic state much more easily than potassium, so that if required on a large scale, it might be pre- pared at a price but little higher than that of zinc. Sodium is a brilliant yellowish white metal; in color resembles silver, while potassium resembles mercury ; is not quite as oxidizable as potassium, but it nevertheless tarnishes instantly on exposure to the air, and must be preserved in naphtha ; is the character- istic alkali of the animal kingdom, its salts being found in all animal fluids ; is so soft at ordinary temperatures that it yields to the pressure of the finger ; it does not become brittle at 32° ; it melts at 194<=', and boils at a red heat, forming a colorless vapour. It burns in the air with a bright yellow flame, and de- composes water with lively effervescence, but not with flame unless the water be hot or in the form of iccj or be rendered thick and viscid by gum or starch. 305. Sodium forms numerous compounds with the metalloids, Which, generally speaking, very closely resemble the corres- ponding potassium compounds. The only compounds of sodium that are of much interest are the protoxide and the chloride. 806. Cbloridr OF Sodium, Symb. Na,Cl, is the common or kitchen salt, and was foimerly incorrectly called muriate of soda. It occurs native abundantly as rock salt in beds which are found in geological formations posterior to the coal. The most celebrated salt mines are those of Cheshire and Gloucestershire in England, Salzburg in Switzerland, Cordova in Spain, and Wieiitska in Poland ; the last named is of enormous extent, and is capable of supplying the entire world for ages. Salt is also largely ob- tained by the evaporation of sea-water, which contains about 2-t per cent, of chloride of sodium. Salt is a white solid ; crystallizes in cubes without water ; is not deliquescent when pure ; decrepitates when heated, owing to the water between the plates, or to unequal ecpansion ; is ftisible at a red heat, and volatile at a white heat ; has a spec, grav. of 2*125 ; is very soluble in water, and but slightly more 80 in hot than in cold water ; is not soluble in alcohol. By the action of sulphuric acid salt yields hydrochloric add and sul- m- easily than ight be pre- Sodium is ibles silver, bS ozidizable on exposure e character- found in all hat it yields ittle at 32° ; y a colorless ime, and de^ i with flame be rendered 3 metalloidS) the corres- ds of sodium chloride. common or Hate of soda. ch are found at celebrated » in Engbnd, Wieiitska in is capable of ) largely ob- ntains about hout water ; eated, owing spangion ; is ; has a spec, lightly more hoi. By the icld and sul- SODIUM. ' 83 phate of soda. It is much used as an antiseptic in curing meats ; is extensively employed as a condiment, and seems to be essen- tial to the healthy functions of the animal economy, giving hydrochloric acid to the gastric juice, and soda to the bile ; is valuable as a source of soda and its salts, also chlorine and hydrochloric acid ; is employed in agriculture as a manure, and is used as a flux in the manufacture of earthenware. 807. Soda, NaO, is a white powder, which rapidly attracts moisture from the air, and becomes hydrated oxide of sodium commonly called caustic soda, which is NaO, HO, Caustic Soda is a white semi-transparent brittle deliquescent solid, which closely resembles caustic potash. It is fusible at a red heat, and is decomposed by a white heat. It unites with acids to form salts which are similar to those of potash, but which are distinguished from them and indeed from those of all other bases, by their greater solubility, and by their communi- cating a rich yellow tint to flame.* The principal salts of soda are the following : — Carbonate of soda, NaO,COi+lOHO Bicarbonate of soda, HO,COt+NaO,COt Sulphate of soda, NaO,SOi-{-lOHO Sulphite of soda, NaO.SOt Hyposulphite of soda, NaO^StOi+SHO Nitrate of soda, NaO.N06 Biborate of soda, NaO,2BOa+imO Tribasic phosphate of soda SO,2NaO,POs,+24iHO Pyrophosphate of soda 2NaO.POs,+lOHO Motaphosphate of soda NaO.POs Hypochlorite of soda Nao'filO Microcosmic salt is a tribasic phos- phate of soda, ammonia, and water = NaO, HO, NHiO.POs, + 8 HO 308. Caebonatb op Soda NaO, CO^ -}- lOHO is the soda of commerce; NaO, CO^ also crystallizes with HO, 5H0, 6H0, and 8H0. The common carbonate is much used as a source of the other soda salts, and in the mflnnfacture of soap and glass. Trona is a native sesquicarbonacA .f ^uda. * The salts of potash impart a pink ^. violet tint to flame fand thoM of 7f ronua a red tint. 84 LITHIUM AND AMMONItTM. 309, SoLPHATB OF SoDA, Glauber's salt, exists native ia Spain, Switzerland, and elsewhere in mineral springs, NiTBATH OF SODA or cubic nitre, is found abundantly in the soi' in certain parts of South America. It cannot be sub- stituted for saltpetre in the manufacture of gunpowder on ac- count of its hygrometric nature. Borax or biborate of soda exists naiWe in India and Persia, and is extensively employed in blowpipe experiments as also is microcosmic salt. Sulphitb OF SODA is much employed in analysis as a deoxidizing agent and by calico-bleachers as an mtichlore. Tot tbibasio phosphatb or common phosphate 2NaO,HO^PO^ is used medicinally and is employed in analysis as a reagent. There are two other tri- basic phosphates, viz. : the subphosphate 3iVaO,P 05+24^0 and the acid phosphate NaO, 2H0, POs + 2H0, There is also a second bibasic salt— the acid pyrophosphate NaO, HO, POg. LITHIUM AND AMMONIUM. 310. Lithium is the metallic base of a very rare aikaliiie oxide known as lithia which is found in small quantities in certain minerals as lepidolite, petalite, &c. Its salts bear a close re- semblance to those of potassa and soda and are distinguished by their tinging the flame of the blow-pipe of a red color. 311. Ammonium is as before stated a strictly hypothetical body as also is its oxide NH^,0. By the action of the voltaic pile a very peculiar amalgam of ammonium is formed with mercury during the electrolysis of ammonia, but it is instantly decom- posed by disconnection with the battery. Moreover the salts produced when ammonia is acted upon by the hydracids are precisely analogous to the corresponding salts of potassa and soda. ts native in al springs, undantly in not be sub- vder on ac- ate of soda ly employed . SULPHITI lizing agent PHOSPHATS ciually and other tri- f24J?Oand re is also a calii.e oxide in certain a close re- Jtinguished olor. Btical body oltaic pile ^.h mercury ly decom- r the salts racids are otassa and OALOItTM. MBTiXS OP THUS ALKALINE EARTHS. LECTURE XIX. CALCIUM. 812. OALcruM, Symb. Ca; Equlv. 20; Spec, irrav i-B^fi wi.. Durnt earth," a term long applied to lime. J^tT ^f * >^"°^J»^-^hite very oxidizable metal • is verv malleable ; is softer than gold ; Is fusible at a red heat when heated m the air it burn, with a brilliant white Hg^^^^^^^ Illations ; ft also burns with vivid H«.ht i„ i , . iodine, or sulphur vaDorr I It^ '^^°''^'''' *''°°^^^«' amalgimates wUhlZ^. '^^""^^^^ ^^^'^ -d readily 313. The principal compounds of calcium are- Lime or protoxide of calcium Chlorideof calcium,. ^"^^ Fluor-spar or fluoride of i'lrtu^^^^^^^^ J«^^ Sulphide of calcium . ^'^^ Caa 314. Protoxidb of Oaloium 0.. LivB. Svmb Can ,'«^>,* • A .ohd i has a spee. gravil, of 308 ; U „„, ..ribl.^«t », » very high temperatufe i slowly volMlUzes .1 ' h-T? . - remarkably ,„„too«. when l,:^^^^ u:^"^ ^^^ hydrogen blowpipe, and I. henee used in the DruV^ooad lie^' It« a d,s metly alkaline e»rth, eansOc and acrid is a bow S,! base ; moistened with watai- it .„i. u ' Powwful foil. L A . ' '' "»«"•) becomes Tery hot and 1280 parts of water at 212* to dissolve it Th« «.,7i. o/«« is merely the hydrate im^l^Ll"::^^ "' "«- .™r. t,?."'!!'" ".""?!'»' '' >""»' P«P0«.. It is of v,„ " " "•=' "• '"" «»r,"iK«dient of mortars and as an agri- a 86 CALCIUM. cultural fertilizer. As a manure it oxidises and decomposes the insoluble organic matters found in the soil ; it decomposes clay and renders its potassa soluble, and it restores to the soil the calcareous matter carried oS by the crop. As a mortar it is mixed with two or three parts of sand and made into a paste with water. The mortar particles at first cohere by the attrac- tion of aggregation, but by degrees the mortar absorbs carbonic acid and the lime passes into the state of carbonate. Hydraulic lime or hydraulic cement is made by burning to« gether limestone and clay. 915. The principal salts of lime are the following :— Carbonate of lime CaO,COt 3vilphate of lime CaO.SOz Phosphate of lime ZCaO,POs Hypochlorite of lime ...CaO, CIO 316. Gabbonatb of Limb CaO^ CO^ exists native abundantly as limestone, chalk, marl, marble, calcareous spar, arragonite, shells and oorals, Sco. Carbonate of lime is insoluble in pure water, but is freely taken up in water containing carbonic acid. Since most river and spring waters contain carbonic acid, they also contain car- bonate of lime which is deposited when the water is boiled or exposed to the air so as to part with the carbonic acid ; in the former case it constitutes the fur of kettles and boilers, and in the latter case the stalactites, stalagmites, and other calcareous formations of caves, Ac. Carbonate of lime is decomposed by all acids except hydrocyanic ; is much used as a source of quick or caustic lime, as a manure, as a flux, as a building material, &c. 317. SuLPHATB OF LiMB, Symb. CaO, SO^ ; Spec. grav. 3*000 ; is not very soluble in water, one part of CaOfSO^ requiring 500 parts of water to dissolve it. Gypsum is the native hydrate of the sulphate, symb. CaO,SOi-\-2HO, and when this is kept heated for some time to about 280° it loses the two equiv. of water and becomes plaster of Paris, the setting of which depends upon the re-absorption of these two equiv. of water. Anhydrite 13 Xia. IlKllTV CIS! I':S"t-.V -,-•• f -r-' •• ■• - 2 3IAONE8IUM. i decomposes the lecomposes clay to the soil the a mortar it is ie into a paste e by the attrac- ibsorbs carbonic nate. I by burning to* svmg :— me SCaO,POi t]ime,..CaO,ClO itive abundantly spar, arragonite, 3r, but is freely Jince most river a,lso contain car- iter is boiled or nic acid ; in the d boilers, and in other calcareous decomposed by a source of quick uilding material, pec. grav. 3*000 ; O3 requiring 500 aative hydrate of hen this is kept he two equiv. of jf which depends iter. Anhydrite i wa.ti>r ! aelenite 8? iwcuw It u removed to . iOT,tVxtonTI,. i, ' ^l** '*"°* '"^""V water. "^ "'™' "'' '"'"'»» »■• by mliing with lima 318. Phobphati or Lim Thera eiiat «B™r<.i j-..- . ^ Phaf, Of lime, the trib«ie phoaphate. beiar ' I. 3 CaO, PO5 11. 2 CaO, ^O, PO5 HI. CaO, 2 ^0, PO5 native in oo^binatior^X";, create t .t" ""- Apatite which is CaF+3 (30aO,Po!) "" po™.rs;rrarctr;.zn '™" ■" ^"" »■' «"«""« Ume ,0 the action of olltTh., •i"'"'"" ""' ''^'™"' °^ 2CoO+2CT= Ca«+CaO,ao The bleaching powder of commerce, if newly prepared con penent" B?ea'l-"°'- "'Z'"'"""'' "•" '^°"> -t'Sano' adilfectan 7r''''"'''"°J''°y'« '" bleaching and « a diamfectant; acxds decompose it and liberate the chlorine MAGNESIUM. wrdl!3r'th?;arl'.tB- "■ «^"- «-• '" was originally bronghtC Z^!Z^- ^r" X"" f^^bl! "'"'^.T^'^ """-■" ™tal ; i, hard, and malSe • IS fusible at a red heat ; is slowly oiidized by water • .n^iT ' With, brilliant white light when heated ^ ^ ''J,,' ^Vr^ vapour. ' ' » *) "" ^ 88 BARIUJI. * 1 321. Maqnbsia, Symb. MgO, is obtainnd by ruasting the carbon- ate ; it has a spec. grav. of 3-610 ; forms a protohydrate with water; is nearly insoluble, 1 part of JtfjgrO requiring 65,500 parts of water to disHolve it ; when prcsptit in lime, it greatly modifies the nature of the lime, preventing the quicklime from becoming mild, and thus rendering it unfit for agricultural purposes ] when pure, it is called calcined magnesia, or magnesia usta. 822. The principal compounds of magnesia are the follow ing :— Carbonate of magnesia (nout -al) MgO, CO^. Magnesia Alba, 3 {MgO CO») + MgO, HO + bHO. Sulphate of magnesia (Epsom Salts). MgO, S O3, IHO. Besides these, there are various silicates of magnesia, as Steatite or Soap-stone, Meerschaum, Chrysolite, Serpentine, &c. Augite and Hornblende are essentially double silicates of magnesia and lime. Dolomite or Magnesian Limestone is a double carbonate of magnesia and lime = (MgOjCO^ + CaO, CO^.) 323. SuLPHATH OF Magnksia or Epsom salts, occurs native as an efflorescence in some parts of Spain ; is found in certain springs of water as those of Epsom and Cheltenham in England, and Sedlitz and PuUna in Bohemia; is prepared from bittern or mother liquor of salt by r v nporation and crystallization, the, rough crystal being cn^ :«1 puigle Epsom salts, and those obtain- ed by a recrystallizati'.fi'i d' ible Epsom salts ; is also obtained by saturating dilute sulphuric acid with magnesian limestone, and, upon the precipitation of the sulphate of lime, evaporating the clear solution and crystallizing the sulphate of magnesia. Epsom salts crystallizes in fine needle-like rectangular prisms with 6 equivalents of water, but the amount of water and the form of the crystals depend to some extent upon the temperature of crystallization. The salt is very soluble in water, 100 parts of cold water taking up 68, and of hot water 150 parts of the salt. BARIUM. 324. Barium, Symb. Ba; Equiv. 69 ; Spec. Grav. 4*000, was dis- covered by Davy in 1808, named by harus " heavy " on account of the great density of its coraponndSj occurs in considerable abun- ¥ le carbon- Irate with ,500 parts y modifies becoming les; wheu le follow - + iHO. IS Steatite . Auglte ;nesia and carbonate native as lin springs ;land, and bittern or ation, the, >se obtain- atained by tone, and, irating the magnesia. iar prisms id the form erature of 30 parts of 3f the salt. 0, was dis- account of 'able abun- dance com ,ined with oxygen n, .^th acids. Barium ia a white, mallerole, rather lustrous metal ; fuses at a red heat and higher temperature volatil .; bIo ly oxidires in air au » a high temperature burng , i^comj water with energ, ordinary temperature ,. *^^ 326. The principal compounds of barium are: Baryta or proto Adc o f bariu n^ n Chloride of ! -iriura ZSZ'ZZZZ'boCI ' Wk!' ^.^'"''^^ '' ^"^^''^ ^y ^"**^"« *^« °>trfl* .f baryta to bnght redness u^ no more fumes are given off. .t is a er^ fa-avy grey porous tvass, whichabsorbs water on expos, fu s at dull redu.ss and becomes crystalline on cool is soluble in 2 parts of boiling or in 20 parts of cold wat. ad by cont,„,ed exposu - the air passes into carbonate o. .aryta ise h rate of baryta and all its soluble salts are eminenUy i 7. The chief SBltB ryte are : Nitrate of baryta, i> „ .,„ Sulphate of b•ryt^.,..■.■.•.•.•:.•I.• Sfn' Carbo^te of ba-^ta. ZZZZZ:^ col STBONTHJM. in f 80*8 ^™°''"™'. Sj-b- Sn Equiv. 44, was discovered by Davy m 1808. It IS a wh.te metal, heavier than oil of vitriol- in which I ove'rid™irr,i "z 'r-""" '" '^""'"-^ "-- " - aiscovered. Its salts and other compounds ' r a vei close r semblance to the corresponding compounds of barium and a e d.8tmg„,shed by the red tinge they impart to flame. li IMAGE EVALUATION TEST TARGET (MT-S) ^ 1.0 I.I ■- IIIIIM I4£ IM 2.2 I ZO 1.8 ■ 1.25 1.4 1.6 •4 6" - ► y] <^ /] ^;; 7 Photographic Sciences Corporation 23 WEST MAIN STREET WEBSTER, NY. 14580 (716) 872-4503 ^ "^ %' '% ^ ^ ^ :\ \ ^ i 90 ALUMINUM. METALS OF THE EARTHS PROPER. i LECTURE XX. ALUMINUM. 820. Aluminum, Symb. Mi Equiv. 13-7; Spec. Grav. 2-500; wfts discovered in the year 1808, by Davy, in clay, and was named from aXuvMn^ the Latin name of alum. Aluminum is an iron-grey solid, having but little metallic lustre ; is almost infusible ; is combustible ; is not acted upon by water ; is hard and very sonorous ; is rather malleable and ductile ; forms alloys with copper, silver, and iron, but not with lead or mercury ; its alloy with copper is very hard, and takes a high degree of polish. 330. Alumina oe Sbsquioxidb op Aluminum, .^ZjOj, exists na- tive, almost pure, in the Sapphire, Ruby, Topaz, Corundum, &c. (Emery is an impure corundum). It is obtained by adding ammonia to a solution of alum ; it is a white, tasteless solid, insoluble in water, and without action on colored tests ; is highly hygrometric ; when moist and freshly precipitated, it is remarkably plastic, and hence its use in pottery, &c.; it has a strong affinity for organic fibre, and also for coloring matter, and is therefore used in dying as a mordant (French mordant, "biting"). The pigments called lakes are made by precipitating solutions of coloring matter by alumina ; is a most powerful absorber of ammoniacal salts, and hence one reason of its great value as a manure. 831. The principal compounds of alumina are the alums and the silicates. An alum is a double-salt composed of sulphate of a protoxide combined with the neutral sulphate of a sesquioxide and crystallized in cubes or octahedra with 24 equivalents of water, its (^ ^neral formula being : M0,S0, + JtffC/j,3S0, + 2iH0. R. Grav. 2-500; ilay, and was little metallic ot acted upon malleable and a, but not with ard, and takes 2 O3, exists na- >orundum, &c. led by adding tasteless solid, lored tests ; is irecipitated, it ottery, &c.; it 10 for coloring ordant (French < are made by nina ; is a most e one reason of le alums and the >{ sulphate of a sesquiozide and alents of water, ALUMINUM. J)t 832. The principal alums and their formulas are : Potash-alum KO.SOz-^AhOzflSO^+uffO. I'l^^T" ^«0. SO,i.AhOtJiSO,+i^O. Ammoma-alum Nff.o, SO^+AhO, 8S03+24Jff O. Potasb.iron.alum KO, SOi+FeiO^.SSOa+iiEO. Sod».mangan«8e.alum XaO, S03+.!f»303,S503+24fl-0. Ammouia^;hrome.alum jvjy.o, SO,+Cr»Oa,SS03+i4>SO. 333. The siLiOATBs OP ALUMiKA are very numerous and con- stitute a large portion of the solid crust of the earth. The principal are the following : Potash Feldspar jrO,5fi03+^/2 03,3-8-103. Soda Feldspar called albite. Lithia Feldspar. Lime-Feldspar. Mica is a double silicate of M^O^ and KO, the latter being often replaced by CaO, or JfejOg. Hornblende is a compound silicate of jII^O^ with lime, magnesia and oxide of iron. Granite and gneiss are compounds of Quartz, Feldspar and Mica. Clays are hydrated silicates of alumina, the purest being kaolin M^O,,SiO, -|- 3H0. This particular variety is employed in the manufacture of porcelain and is produced by the disintegration of feldspathic rock. Potter's clay contains iron, and hence its red color. Ochres are clays colored by iron. Umber and sienna are clays colored by iron and manganese Fuller's earth is a peculiarly absorbent clay. Many varieties of slates are nearly pure clays. Emerald or Beryl is a double silicate of alumina and glucina. othbb mbtals of class iii. 334. Gluoinum, Yttrium, Thorium, Zirconium, Erbium and Terbium are the other metals belonging to the class of me- tallic bases of the earths proper. They are found only in small quantities, and for the most part only in very rare minerals, m general appearance and properties their oxides closeiy ds ZiNO—rNIOKEL— COBALT. METALS PROPER, OP WHICH THE PROTOXIDES ARE rSOMORPHOXJS WITH MAGNESIA. ZINC. 835. ZiHC, Syaab. Zn; Bquir. 32-5 ; is a bluish white, lustrous, lamellar, crystalline metal, brittle at ordinary temperatures, malleable at 2ia«> P. and brittle again at 400« P.; fuses at a red heat and boils at a white heat; all of its salts are poison- ous. SSe. The compounds of zinc are chiefly the oxide ZnO, and the chloride Z»CZ and the principal salts of the oxide are : Carbonate of zino, zine bloom, eal(mine,...2(ZnO,COi) + Z{ZnO,HO), Sulphate of zinc, white vitriol, ZnO, SO3, + 7JffO. NoTB. The oxide of zinc is emplpypd as a white paint in place of white lead as it possesses the advantage of not being dangerous to the workmen, and of not being bhwskened by sulphuretted hydrogen. Sulphate of zinc is employed by dyers and is used as an emetic, but is poisonous in large doses. NICKEL. 887. NiOKii,, Symb. At; Equiv. 29-5 ; is found rather abundant- ly in nature ; often associated with iron or arsenic ; is a greyish white lastrous malleable and ductile metal; is attracted by the m^net ; is about as fusible as iron, and, like iron, decomposes water at a red heat. 838. The principal oxide of nickel is the protoxide, and it tfther chief compounds are the chloride MC? and the proto-sulphide NiS. The protoxide combines with nitric acid to form nitrate ofnickelAtO, J^O, + eHO and with sulphuric acM to form sulphate of nickel KO.SO^^IHO. These and most other salts of nickel are of a fine .green color and are poisonous. COBALT. 339. CoBAi^T, Symb. Co; Equiv. 29*6 ; is al>out as abundant as nickel, and bears a very marked resemblance to thatmatal in nearly all its properties. Its name is derived from tiie KoboIdB, or evil spirits of the mine, and was given to it by the ignorant German miners of the middle ages who were frequently deceived by the CIDGS ARE lite, lustrous, emperatores, ; fuses at a 3 are poison- ZnO, and the .re: Z{ZnO,HO). place of white the workmen, ilphate of zinc onoos in large erabundant- is a greyish attracted by 1 decomposes , and it other oto-Bulphide form nitrate .cid to form most other onous. abundant as ital in nearly K>lds, or 6Til ant Qerman »Tedl>y the CAOMirrU — COPPER. ^ fnin .r I VI '"^ ""*''' ^^''^ ^^'•^ nevertheless raluelee. nntil the close of the 16th century,when they were first employed for coloring glass. Cobalt is attracted by the magnet. There wl'''''?^ri^'' °^"°^*^*' ^' P'°*^^^« ^ ^^^^ and combines with acids to form salts, which are red when hydrated, but blue roilonous.''**'' "' '^^"*'°" '" ''''"''^' '^'*' "^''^^^^^ '"^"^ ^' CADMIUM. Knf*^; .^f'*"''^ ^' *'°'*''^ *" ''**^'*' °^*®*y associated with zinc but not inlarge quantities. In its physical properties it resemble, tm It has one oxide, viz : the protoxide ; but neither the w!' -""l^ *''» "'*' *^^ °*'**^ ^*'«^^" «f a°y practical impor- tance m the arts. LECTURE XXI. COPPER. 541. OoPPM,Symb. C«.(cupmm) ; Equir.32; isaTedi.itrous Tw 'Z!^ "?! ^^'^^ ai»d ductile, ranking in the former respect neit aftfer gold and silver, and in the latter next irfterplatinmn, gold, silver and iron ; in tenacity comes ni^xt to iron ; is the mosi sonorous of metals; its spec. grar. varies i^m B-lB to 8-96. fuses at a red heat and is somewhat volatile at a ^hite heat, itj iZ'I* "T* ""'f * '''^^^* ^'''' ^^ 5 ^ precipitated from Ton^T'^.^"'^^''''^'^''^''^'' <>«per is preci- i not altered tallic copper, d combines ; ical interest ; I for coloring )ften bronzed the action of by exposing >f copper. a very hygro- of copper ; is ^en at a low acids to form )lue or green 1, and are in us, but their counteracted cupric salt to r antidote for :h forms with lie following : + 3JI0. \-6B0. h03)-\-SO. iH303)-\-mo. CuOi+BO. 5 (CuO, AgOs). D copper with 'he salt- crys- and are very considerable 347. Sulphate of ooppkr, blue vitriol, blue ttone, blue cop- peras, may be formed by dissolving copper in sulphuric acid diluted with half its bulk of water, and then crystallizing ; the crystals are fine transparent blue oblique rhombic prisms which dissolve m 4 parts cold or 2 parts boiling water, but are insoluble in alcohol. Sulphate of copper is used in galvano-plastic as a source of copper, and in medicine as an emetic and an escharotic ; is also employed in dyeing ; is very poisonous. LECTURE XXII. MANGANESE. 1 /fnt®' ^^''^^=^«' Symb. Mn; Equiv. 27-5 ; Spec. Grav. about 7 000; was discovered by Gahn, in the year 1775, in an ore previously examined by Scheel, and called manganese (also magnestantgra) ; is a greyish white, brittle metal, very oxidiz- able, and is best preserved in naphtha. 349. The compounds of manganese and oxygen are five in number, with two coiipound oxides. They are as follows :- Protoxide or mangano\ s oxide,...,ilfnO. Sesquioxide or manganic oxide,....JIfn2 O3. Bmoxide or peroxide, MnOi Manganoso oxide or red oxide Mnio\ or MnO+MmO^. »^!!S^s;::::::::::::::::::::Sj^: *:' ^«^' + ^^- Permanganic acid, Mn^O?. IRON. T fn?* ^''°^<^**- ^«"'^«»)' symb. Fej equiv. 28 ; spec, grav 7-700; was known in very ancient times; has a bluish-grey color, and a strong metallic lustre ; is very ductile, moderately malleable, and exceedingly tenacious. Its melting-point is very high (27860) ; it becomes pasty before it melts, and is then capa- ble of being «,eJd.rf, and also of being hammered or moulded into any form ; is magnetic, and in the form of steel may be made r Ovv »v, u«L cue magneusm of soft iron is very transient ; ^ IRON. oxidizes very slowly in dry air at ordinary temperatures, but rapidly in moist air or when heated ; burns in the air at a white heat, or in oxygen, in which it throws off brilliant scintillations. 861. The principal compourids of iron are the following: Protoxide of Iron FeO. Sesquiox. or Ferox. of iron, . .¥»t Oz . Black oKide of iron F03O4. Ferric add, FeOa. Frotoohloride of iron Fed. Perchlorlde of Iron, FesCh. Protoiodide of iron,. Fel. Protosulphide of iron, FiS. Seaquisulphide of iron FeaSz. Bisulphide of iron, FeSt. 352. Protoxdb or Fbrbods Oxidb«of Iron, feO, is a very- powerful base ; is almost unknown in a separate state, owing to its tendency to attract an additional quantity of oxygen and become peroxide ; it combines with acids to produce salts, which have generally a pale green color, though some are colorless. 863. Sbbquioxidb or Iron, Pbroxidb or Iron or Ferric Oxidb, FtfO^f is a feeble base; is isomorphous with alumina; is not magnetic; with acids it forms salts, which are in color either yellow, brown, or red. 864. BiriOK OxiDi or Iron, Magnbtio Oxidb ; Loadstonb ; Fe^O^ ; is regarded as a mixture of protoxide and sesquioxide, t. «. Fe^ O4 = Fe O+Fe^ O3 . It is incapable of forming salts. 366. Fbrrio Acid, FeO^j corresponds to manganic acid, and, like it, has never been isolated. It forms salts called /erraie*. 366. Protobulphiob or Iron is much used as a source of sul- phuretted hydrogen ; the bisulphide occurs native crystallized in cubes, under the name of iron pyrites, and is sometimes used as a source of sulphur. 367. The principal salts of the protoxide of iron are : Garbonatb or Iron, or Gabbohavb or thb Protoxidb or Iron, jFeOjCO,, \»L:''*h occurs native in chalybeate waters, and also in fifpathoze iron-ore and clay iron-stone. Pbotobulphatb or Iron ; Sulphaxb or tbb Protozibi or Ibom ; Fbrbous Stopsatb ; Grun Vitriol or Copbbras, FtOfSO^ H0+6H0 LEAD. 97 »eraiure8, but itir at a white )cintillation8. Jllowing : FetCh. Fel. 1, FeS. m FeaSi. FeSt. sO, is a very- tate, owing to ' oxygen and e salts, which e colorless. ?'krrio Oxidk, imina ; is not L color either LOiDSTONl) ; 1 sesquioxide, ning salts. « nic acid, and, led ferrates. source of sul- :rystallized in times used as are:— >xiDX or Ibon, e waters, and xwi Of l&oir ; AS, FeOfSOt Pbotomitbati or Ibon; Nitrjltb of thi Pbotozidi of Ibob Pbbbous NiTBATi, FeO^NO^. 880. The principal salts of the peroxide of iron are :— Pbbsulphatb of Ibon, Sulphatb of thb Pbboxidi, Pibbio Sul- phate, jv, 03,3503. FiBBIO OXALATl, i^,0„3C«0,. Fbbbio Aobtatb, Fe^ O^^iC^H^ 0,. 868. The principal ores of iron are the following:— I. Clay Ibon-btonb— a carbonate of the protoxide, generallj containing lime and magnesium. II. Spathic Ibon-obb— crystallized carbonate of protoxide. III. Rid Hbmatiti— pure peroxide. IV. Brown Himatitb — hydrated peroxide. , V. Spkoulab Ibon-obb— crystallized anhydrous peroxide. VI. Black Oxidb ob Magnbtic Oxidb of Ibon. VII. Black Band— a variety of compact clay iron-stone, cou- taining bituminous matter. VIII. Boo Ibon-obb— a mixture of hydrated peroxide and'phos- phate of iron. IX. Iron Ptbitbs— a bisulph'ide of iron, and employed as a source, not of iron, but of sulphur. LECTURE XXIII. LEAD. 869. Lead, Symb. Ph; Equiv. 104; is obtained principally from the sulphide (galena) by roasting to expel the sulphur, but there are numerous other ores of the metal. Lead has a spec. grav. of 11'445 ; melts at 612« P., and shrinks considerably upon solidi- fying ; like most other metals assumes the octahedral form upon crystallizing ; not very easily oxidized when massive, but exposed to the air its surfiice soon tarnishes by becoming covered by an exceedingly thin film of oxide ; is not affected by pure water free from air at the ordinary temperature, but if air be present the lead is oxidized at itg «jrTu>nRA and <« hon^o f»..«.t :.. *\^ 98 LEAD. water; if carbonic add or sulphuric acid be present in the water, it combines with the oxide of lead thus formed, and the salt is deposited upon the metal and being insoluble protects it from further oxidation ; hyice soft or rain water cannot be safely employed for domestic purposes if preserved in leaden cisterns, but hard water is less contaminated. 360. The principal compounds of lead are the following : Suboxide of lead, PfioO Protoxide of lead, massicot, litharge, "'pj O Besquioxide of lead, ZZ.3".....P4«Og Binoxide of lead, puce oxide, plumbic acid, ./.^"...'.'...Pb Oj Minium or red \e9d,plumbateqflead, (2PJ0 + pioj) = P63O4 Chloride of lead, , pj d Sulphide of lead or 0ra2«»a, ...".....".*."...!.P6S Oxy-chloride of lead, mineral, Paris or Turner's yellow,Z....PbCl, IPbO. 361. The only oxide of lead that is salifiable is the protoxide; this is called massicot when it has not been fused, and litharge when crystallized by fusion. PbO is soluble in 7000 parts of distilled water but is much more soluble in water containing sugar. All of its salts are poisonous, but none eminently so. The sub-acetate is a more powerful poison than the carbon&te. The sulphate of lead is insoluble, and hence sulphucic acid and soluble sulphates are employed as antidotes for lead. A compound of litharge and lime is used for dyeing the hair of a purplish black color, the change of color being due to the action of the sulphur of the hair, which, with the lead, produces black sulphide of lead. 862. The principal salts of the protoxide of lead are the fol- lowing : Nitrate of lead, PbO, NO s. Sulphate of lead pi,o, SO3. Carbonate of lead, ceruse, white lead, PbO, CO 2. Chromate of lead, chrome-yellow, PbO, CrO^. 363. Gabbonati of Lhad is an invaluable pigment, is insolu- ble in pure water, but dissolves in water containing carbonic acid or any other acid which forms a soluble compound with its base ; is blackened by sulphuretted hydrogen, hence the blacke^ing TIN. 99 I the water, the Bait is eCbS it from t be safely en cisterns, )wing : PbiO Pb O PbaOt Pb Ot 3«) = P6304 Pb CI , PbS ..PbCl, 7PbO. protoxide ; >nd litharge it is much s salts are is a more of lead is Iphates are tharge and : color, the hur of the lead. re the fol- SO3. CO 2. CrOi, f is insolu- rbonic acid h its base ; blackeAing of common white paints in stables and other places where that gas is eTolved ; is also employed in glazing cards. METALS PROPER ALSO HAVING ISOMORPHOUS RELA. TIONS WITH THE MAGNESIAN FAMILY. 364. The only metals of much practical interest or importance belonging to this class are tin, and chromium. Of the others vanadium and tellurium are among the rarest of the elements. ' TIN. 365. TiH, Symb. 5fn., (stannum) ; Equiv. 59 ; is a white metal with a faint tinge of yellow, one of the softest, and most malleable of the metals ; possesses but little elasticity and tenacity ; has a great tendency to crystallize, the crackling noise heard when a bar of tin is bent is due to the friction of the crystals upon one another ; melts at 442o F. and when poured into a hot iron mortar and continually stirred till cold it may be reduced to powder ; is but slighlty volatile even at a white heat ; but burns in the air at a very elevated temperature, being converted into binoxide ; is not altered by exposure to the air at ordinary temperatures. 366. The principal compounds of tin are the following : Trotojide ot tin, ttatmotu acid, sn O Biaoiide ot tin, atannic acid, '....SnOg Metastannic add, ZZZZZ.......S»6 Oio Protochlorideoftin, sn CI Perohloride or bichloride of tin, .'..!....!."!!!!!!!!!...«» Clg Sulphide of tin, i'^'ll^"^'" "" "^^^^ S Bisulphide, aurum muHvum, mosaic gold or bronze pu ocier,..Sn S2. 367. Protoxide of Tin is obtained from protochloride of tin by precipitation with an alkaline carbonate. Thus obtained It is a white hydrate, which heated to redness in an atmosphere of carbonic acid, becomes black anhydrous oxide ; is also known in the form of olive-green and red powders. When heated in air the protoxide burns like tinder and becomes binoxide. SnO is insoluble in water but is soluble in acids ; with which it combines to form salts which are not very well known. Stannic 1^^ CHROMIUM. AOiD SnO, i» obUIned by precipitating the bichloride of tin. and i« sometimes employed in polishing under the name of Ltty T« *"; r.rj'T."""' ""* ''"' ^' ^^**'"^^ ^y '^^"J"^ fragments of tin in dilute hydrochloric add and evaporating to crystal. ligation. BicHtOHiDi or tiw may ba obtained by saturating a strong solution of protochloride of tin by means of a current of chlorine gas. Both of the chlorides may also be obtained in an iinhydrou* state ; they are chiefly of use as re-agenta and in the process of dyeing. Bisulphidb ot tinJIs prepared in the dry way by igniting a mUture of stannic oxide, sulphur, and sal-ammo- niac in a corered cmoible. CHROMIUM. 868. Chromium, Symb.Cr.Bqui7. 27, exists rather abundantly in nature as chrome-iron and as chroraate of lead ; exists to the extent of about 6 per cent in the ruby ; also gives color to the emerald.* Chromium is magnetic only at very low temperatures ; is very inftisible ; is attacked with difficulty by acids : has a spec. grav. of about 6*9. 36». Tlie principal compounds of chromium are : Protoxide of chromium or chromoui oxide, Cro Sewiuloilde of chromium or ohromlo oxide,...'.'.'.'" Cr,On Chromic add. .; .r.;;;;.;:;;:::^:?,? 370. The principal salts of chromium are those of the sesqui- oxide and the chromic acid, and of these the chief are : SuLPHATB or SiSQUioxiDi OB Ohbomio Sulphatb Ct^O^, 3S0 exists in three forms, viz : the violet and green salts' each containing 15 equiv. of water of crystallization and the red salt which is anhydrous. Ohromati or Potassa KO, CrO,, exists as bright yellow anhy - drous crystals, soluble in water but not in alcohol : poi- sonous. BiCHBOMATB OF PoTASSA, KO, 2CrO„ exists in bright red tabu- lar crystals. Chhomam or Soda, mo, CrO.^iOHO exists in hyacinth red six-sided prisms beve lkd at the ends. reL" ^nv^"" "Tf^ discovered by M. Toumet that the colors 7f gems, smoky quartz, 4c.. are due, not to metallic oxides, as was formerlv sapposcu, out 10 volatile hy'jro.c»rlK,n8. RARE METALS. 101 Ide of tin, and ime of putty ng fragments g to crystal, saturating a f a current of )tained in an Its and in the 1 the dry way id sal-anmo> r abundantly exists to the color to the mperatnres ; icids ; has a OjOa CrOa the sesqui- re: ^f O3, 350, Screen salts, ''stallization ellow anhy> cohol ; poi- ht red tabu- yacinth red the colors of was formerly Ohromat. of LtAV,PbO,erO, is the chrome yellow of painters. 871. The other metals belonging te this class are not likely to fall mto the hands of the student, as they are rare and com- paratively speaking unimportant. They are :— •eltHn^or" ^■* ^''^'' • '*'''"' ''^^^' brittle, nearly infadble metal re- f^r th«? '^« " ""1^- '^^' ^<^^^^i^ of Ammonia is employed tn analysis andlve^uidt^'^^^ "' ^""°"^" ""^ '°""' '""^^ "^^°^^- SJL J^I i^S in?^^r'!i,"*^«'"'"«'^^ '«'"« two or three Slir?o«-^0,i^oV\T?^^^^ '" intermediate or blue TBLruaTTTM tI L"^. • "*l''o'or»88«veraIchloride8.8ulphide8.Ac. Is a n^. ; : ^' ^ * ''"'y "''^ ""«**^ resembling silver in appearance meXdsrtT.^'K^' '''*' r** ^^^^'"^^^^y- *"^ «° "«"'y r«««^bles the mark«^ - A? ^^ '"""^ *'*'^'"*'*' *'''««*^ ^"h *1^«°> »"d forms a w^U- m,^k^ group with Sulphur and Selenium, which it greatly resembles^ «nrn?!!!% ?.u'[''*^' T«»"™'*'' ^^id. TeO,, and Telluric Acid. TeO^, a Die the corresponding compounds of sulphur. JL71^'!^1L ^t^a "/ "*''®' «0PP«''-''ed. infusible metal, having a spe . grav. 8 3. Is chiefly found combined with iron in certain parts of the o^k^'f^""^ " the titaniforous iron ores of Canada. It combinefw Uh ggJligggdTitank A dd. It also combines with chlorine, nitrogen. Ac. ea^h!"soTfjVrmVJl^^S^^^^^^ element is intermeSte in ^^J«^^ *''*^^u?' , ^" these cases the second the other twn Thf.rTf v, Properties, combining number. &c. between Chlorine. Iodine, Bromine, A gas, A solid. A liquid. Very strong affinities. Much weaker affinities. Intermediate affinities, Equiv. 36*5. Equiv. 127. £q. 127+36-6 -^— =81-26 So also the equivalent of Sulphur is 16; of TeUurium it is 64-2.that pf Selenium being about }1±^ ^ ^^^ ^^ ' "*' H 102 BISMUTH — ANTIMONT. METALS ISOMORPHOUS WITH PHOSPHOROUS. LECTURE XXIV. BrSMUTH. 372. Bismuth, Symb. Bi, Equir. 213 ; found abundantly in the metallic state chiefly disseminated in quartz rock ; is also found as an oxide, a carbonate and a sulphide ; has a greyish white color with a red tinge and a metallic lustre ; is very brittle and crystalline ; fliees at 480<> F., and volatilizes at an incipient wMte he&t ; fused bismuth expands in the act of solidifying and hence its use in type metal ; is not acted upon by dry air, but tarnishes if moisture be present ; hac a specific gravity of 9*664. 878. The principal compounds of bismuth are the following :— Binoxideof bismuth, Bi Oft Teroxide of bismuth, Bi O3 Quadroxlde of bismuth Bi O4 Feutoxide of bismuth, bismuthic acid, Si Og Terohloride of bismuth, Bi Ca Bisulphide of bismuth, Bi St Tersulphide of bismuth, Bi 83 874. The Tbroxidb of Bismuth (sc metimes spoken of as pro- toxide or sesquioxide) forms a class of salts which are very heavy white, poisonous, and which exert an acid reaction ; they are nearly all decomposed by water which throws down an almost insoluble basic salt, the acid remaining in solution. The most important of its salts is the nitrate. Of this there are two or three varieties as the neutral nitrate Bi O^SNO^+JSO, and the basic nitrate BiO^NO^ + ^O* ^^e latter is known as hismuthwn album or flake white. The terchloride of bismuth is used as a cosmetic under the name of pearl white. ANTIMONY. 875. Antimony, Symb. 8h (^Stibium), Equiv. 129 ; is obtained from the native sulphide ; the metallic antimony of commerce ii always morc Of loss impure and is capable of being pur-ilied only OROUS. lantly in the is also found reyish white y brittle and an incipient idifying and dry air, but rity of 9-664. ollowiug :— mot BiOz BiO^ BiOs BiCz BiSs BiSz n of as pro- very heavy n ; they are 1 an almost The most two or three id the basic bismuthum I used as a is obtained ommercA ii •i:.j 1 — UliUvU VUijf ANTIMONT. 203 With great difficulty ; is a white brilliant metal of a lamelUt«^ si^ructureanddensityofabout6.75;isnotacteduponb™ to he air ; fuses about 800 P. and volatilizes at a white heat not, ho..ever, sufficiently volatUe to oe distilled ; burns Tn 'th air at a red heut producing abundant fhmes of oxide of antimony! 376. The principal compounds of antimony are :— l^ro^deotMtimony.AniimonoutAcid. i-entoxide of antimony, Antimonic Acid. ff °» Antimonuretted hydrofcon, ^° ^» Terohlonde of antimony, £;«;;;/';i;;«;;^^^^^ fj?^' Tersulphide of antimony ^^ ^^fl Penta-ulphide of antimony; ■^oW;«''^«^Ae^;^-^;i--^^ ^/^ 877. TBBoiaDK OF ANTiKo»y may be prepared 1 aissol vinir the prepared sulphide in about four times its weight^f flC/, Thus the dissolved terchloride is then precipitated as teroxide by adding an excess of carbonate of potassa and boiling, it is a white insoluble body, which crystallizes in ne.dleg, fuses at a red heat and at a higher temperature volatilizes j Combines l^th acids to form salts, which, when soluble, have In add reltT^l' ANXIMO.IO Agio, Sb 0„ is produced by the action of strong 2;^^* aci4 on the teroxide of antimony; it is, when thus prepar!^ a hydrated solid Sb O, + 5H0, slightly ^luble in watering less so m dilute mineral acids ; it combines with bases to form f class of neutral salts, the general formula of which is MO SbZ Most of the salts of antimony are decomposed by water ' * m M (A&o. It IS a soft grey solid ; a powerful caute-y • is deoom«n;I,i k excess of water forming powder of Algaroth. * decomposed by The tersulphide is the common ore of autimony and is ohf «,n^ orange red precipitete when SS is passed tSgTa itn " f «f/°' or one of its salts. Kermes Minerai Is a Sure of sis Vt^" and ^6^5 and an alkaline sulphide.-it is obSrJlilf^Z'*^ ^ pared -lUphide in a solution of caustic potash and theu~adding «i Zh^' 104 ARSENIC. 878. The principal salts of antimony are the following :-^ Antimonate of antimony, Sb 09,Sb Og =3 {Sb O4 Antimonate of potash, K O, Sb Og, + 6H0 Autimonate of lead, Naples Yellow, PbO, SbOg Oxalate of potash and autimony KO, CiOj + Sb O3, 8 Cg O3 Tartrate of potash and antimony, ...KO, ,56 O3 -f- Cg JJ* Oi + 2 HO Note.— The last two salts dilTer flrom the ordinary compounds of anti- mony in not being decomposed by water, the tartrate of potash and antimony, or tartar emetic, potash tartrate of antimony is prepared by neutralizing the bitartrate of potash by means of teroxide of antimony. The oxide of autimony is boiled with four times its weight of water and the bitartrate of potash added in small quantities at a time till all the oxide is dissolved. The filtered solution on cooling deposits the crystals of tartar emetic,— these crystals become white in the air by losing their water of crystallization. This salt was formerly regarded as a double tartrate of antimony and potash KG, C^Hi Oi + SbO^, CiH\Oio, butDumas and Graham and other eminent chemists prefer regarding tartaric acid as a bibasic acid having double the atomic weight formerly assigned to it. Upon this view bitartrate of potash \& K O, H O {d Ua Ova) and substituting one atom of Sb O3 for the atom of water, we get the formula for tartar emetic KCSbOs.iCsHA Oio). The acid antimoniate of potash KO, 2 Sb Ot, is the Antimoniwm diw phoreticum lavatum of the pharmacopoeias. ARSENIC. ^ 379. Arshnio, Symb. As ; Equiv. 75 ; is found in nature usually in combination with sulphur or with other metals as with iron, nickel, cobalt, and copper. The mineral known as arsenical pyrites or mispickel cSmmonly contains iron, sulphur, and arsenic, in the proportions represented by Fe S^ -j- Fe As^. Metallic arsenic may be obtained from the sulphide, or by reduc- ing a mixture of one part of arsenious acid and three parts of black flux and condensing the volatilized metal. Arsenic is a steel-grey lustrous metal, crystalline and exceedingly brittle • rises in vapour at about 356** F. without previously melting. The vapour has a strong garlic odor, ascribed by some to the formation of a suboxide, it has a density of 10*39 that of the metal being about 5-75. Arsenic burns in the air with a pale blue flame, producing arsenious acid ; exposed to dry air it tarnishes : in moist air it becomes craduallv cnnvArtArl intn wing :— = 3(56 04 h. + 6H0 0, SbOs 3,8C8 O3 '10 + 2 zro unds of anti- r potash and I prepared by of antimony, of water and me till all the bhe crystals of tg their water tie tartrate of it Dumas and iric acid as a dtoit. Upon )8tituting one tartar emetic monium dia* ure usuallj s with iron, iS arsenical ind arsenic, .. Metallic by reduc- ree parts of Lrsenic is a gly brittle ; jly melting, some to the that of the n^ith a pale dry air it iTArtArl intn AftSBNTO. 106 arsenious acid. In all of its c& tnations as with oxygen, chlorme, hydrogen, &c., arsenic exhibits a very close and remarkable similarity to phosphorus. hJn°-f i^^'S"*" Ttf° ^"^^ "°* P°^«°^ ""*" «»"««"« after it has b^n swallowed-probably not until it has bren converted into arsenious I^^ioJ. I,?H . r' '""f ^ ^^-^''««'^'- i» » ^i^ture of arsenic with T^Z^ "* ^ ''^'°* *^' ^""^^''^ ""^'^^ ^ *h^ ^''io" 380. The principal compounds of arsenic are the following :— Arsenious acid, . Arsenic acid ."''.'"l"Zx.\\'"!!!!l"\"!."".''.' j* o Arseniuretted hydrogen J^ rr Bisulphide of Arsenic, red orpiment.rmlgar,'. As sl Tersulphide of arsenic, yellow orpiment. King'7yeUowl''miih^r- temouaacid, • x- Pentaaulphide of arsenic, »ulp?iarseni7i^d,ZZ'^^^^^^^^^^^^ gl -N0TB.-The pharmaceutical preparations of arsenic are chiefly the ^H'^ht!r'uT''*^^*""*'''*''''^^«^"P'«P«'«dbyfusing arsenious acd with tersulphide of arsenic, and the liquor arsenicalis, which is a :::!d1n^lrr:f^:L^^^^^^^ ^^^ '- '-^^^'^ '^ dissoMngarsenious 881. Arsenious Acid or White Arsenic is obtained as a by- product in roasting certain ores as those of tin, nickel, cobalt &c., and is purified by resublimation. When freshly prepared' arsenious acid is a transparent massive body, but it rapidly be- comes opaque externally, and the opacity gradually travels towards the centre. Newly prepared jIsO^ resembles glass in appearance while the opaque variety resembles porcelain. The two varieties differ very remarkably in certain respecta ; thus, the transparent form is at ordinary temperatures about three times more soluble than the opaque, and the specific gravity of the latter IS only 3-70, while that of the former is 3U. Arsenious Acid volatilizes without melting at 380° P., producing a colorless, inodorous vapour, of a density of 13-85 ; ^s O, is but sparingly soluble in cold water, but more so in hot water ; 100 parts of water at 6O0 take up only about -25 of a part of jIs O, • the same quantity of water 212° takes up 11^ parts of the acid ' and upon cooling to 6O0 F. retains 3 parts ; it is much more soluble m aiiute aydrochloric acid; both it and its soluble salts are loe ASSSNIO. eminently poigonons ; the antidotes to their action are not very reliable ; the best consists in giving a mixture of hydrate of magnesia and ferric sulphate. The iron of the latter forms insolu- ble arsenate of iron ; and the sulphuric acid combines with the magnesia to form sulphate of magnesia. Otu.^r means taken to counteract the effects of the poison are to produce vomiting if it does not occur spontaneously, and to administer oils, or albumen or hydrate of magnesia, which envelope the particles of arsenious acid and protect the coats of the stomach. Arsenious acid is bibasic, and with bases forms salts the general formulae of which are 2 MO, As O3 and MO, HO, As O3. NoTB.-Arsenious acid enters largely into the composition of bright green paints and colors, as emerald green, Scheel's green, the green color* used m confectionery-the green colors of paper hangings-^and hence the unhealthiness of rooms hung with such paper. /382. Aesbnio Acid, As O5, is obtained by heating arsenious acid in considerable excess of nitric and a small quantity of hydrochloric acid ; (8 parts of AsO^ 4. 24 parts NOg + 2 parts HCl) evaporating the solution to the consistence of syrup and then heating pretty strongly to expel the excess of N 0^ and HCL Arsenic Acid is a white deliquescent solid, very soluble in water, but less so after it has been dried ; it is easily reduced to AsO^ by deoxidyzing agents, as sulphurous acid ; is also reduc- ed by a strong heat, but undergoes fusion before reduction. It may be crystallized by slow evaporation from its solution, but it does not retain either its water of crystallization or its basic water with any great degree of force ; it forms poisonous salts, which, like those of phosphorus, are tribasic, having the general formulas ^M0,As0s, 2M0,H0,As O, and M 0,2 HO, As O^. 883. Absbniurbttbd Htdroobn, As H^jia prepared by acting on zinc, in presence of As O3, by dilute snlphuric acid. It is a color- less gas having a sickly alliacious odor ; is very heavy, its specific gravity being 2-695 ; is soluble in water to the extent of 1 vol. in 6, and is completely absorbed by a solution of sulphate of copper or of nitrate of silver ; it burns in the air with a bluish-white flame being resolved into As O3 and H 0. Arsen- mretted hydroiren is exoeedincrlv poiannnns whAn if>hou*i «.— « re not very hydrate of rms insolu- BS with the 18 taken to mitingifit >r albumen farsenious ms acid is BB of which ►n of bright ?reen colors id hence the : arsenioas uantity of + 2 parts syrup and NOg and ry soluble ly reduced ilso reduc- m. It may )ut it does .sic water ts, which, .1 formulas acting on is a color- leavy, its J extent of f sulphate ir with a Arsen- «*W» - U T \JtM. SILVER. 107 in the smallest quantities ; this is evident when it is remembered that it contains by weight 962 per cent, of arsenic, or tha* one cubic inch of the gas contains i of a grain of arsenic in a finely divided state. THE NOBLE METALS. LECTURE XXV. SILVER. 884. SiLVKB, Smyb. Jig (Argentum), Equiv. 108 ; is a metal of a dazzling white colour ; harder than gold, but not so hard as copper ; very malleable and ductile ; is more tenacious than gold, but less so than iron, copper and platinum ; it has a spec. grav. of about 10-500 ; fuses at a bright red heat, and at a very bright white heat it volatilises slowly ; is not affected by exposure to air even in the presence of moisture, but becomes covered by sulphide in the presence of air contaminated by HS. Fused silver under certain circumstances, absorbs mechanically 22 volumes of oxygen from the air, and upon solidifying evolves it Again, becoming somewhat aborcscent in appearance ; may be obtained pure from silver coin, or standard silver, by dis- soivinig in nitric acid, evaporating nearly to dryness to expel exqesfl of iyOj, diluting largely with water, and suspending a I^te of clean copper, as a clean penny, in the solution of titrate ; the silver is thus precipitated in a crystalline powder, and must be thoroughly washed by decantation. S95. The chief compounds of silver are : Suboxide F., and boils at about 662 F°., yielding a trausparent vapour ; volatilizes slowly at all temperatures above 68® F. The mercury of commerce is generally very pure, but it is some- times contaminated with other metals, as tin, lead, &c., and then has its fluidity remarkably impaired ; may be purified by distilling from half its weight of iron filings, or by digesting it with dilute nitric acid* or solution of corrosive sublimate, either • It shoiUd be agitated in a porcelain dish with a mixture of 1 part nitric old and 2 parts water, the dish and its contents being Icept heat^ to 180" P. ue, and is be fased in in the elec- h tempera- PtO PtOt ?tci ^tSt eat use in part nitric iongistence ain eyapo- lidifieg, on lass, which it is con- cording to latinum is im be pre- 00; spec, ilver) — is solidifies ansparent °F. Tl^e is some- Ac, and urified by gesting it »te, either Dart nitric Bd to 130" P. MIROTTRT. HI Hal« no ''?"**" ^''" '' '^' '^'"'^' «*»'•« °^'d*We than itself, merco" i'Ta ™'l' "' ''•^^'"•'ning whether the equivalent of rr. ^ */ ? ^^'^' ""' ^« *^« *" ignorance of any isomor- lowT ?. ^°^ *^* P'**^*'*'^^*' '^"^ ^«^««d it is very generally sub'ttron ?"h".^' "'"^ '^"^^^«- '"^ hydrated'acidsby substitation for hydrogen; is not affected by hydrochloric or b^nllntlcT'^"^'''"* '' rapidly oxidizLLd dissolve^d 896. The principal compounds of mercury are :— Mbrourous Oxidk, suboxide, black oxide, Hr n ^ Mmboubio Oxidb, peroxide, vA oxide, hJo MIBROUBO08 Ohloridb, eubchloride, calomel, .*.*.*'* hI CI M.EOURIO Ohloeid., protochloride, corrosive eublimate, HgCl M.Rcm»otT8 Shlphidk, mbeulphid^, .' ^^ MaRouRic SuLPHiDB, cintuihor, jc^'« MbBCUROUS lODlDB, MUbiodidc, ,,',,[ ffl T Mbboubio Iodidb, proto4odide ......' ' .' .' .' ' .' ' * jj^j J!L^^T^T ?".'*' ^' °^**^"*''^ ^^ acting'on'calomel with an excess of cold solution of caustic potash ; is a black powder, T. T"' I '! ' ^'J'''^^0''^ by light or heat into metallic .Iir ' T^ ""^'^ '°^°^^' "* decomposed by water, which Tstbrair ' '"* °' ''''' "''' '''' *^'°- ^-'^ - -0^- 898 Mbrourio Oxidb is prepared by several methods, as for example : > "* I. By heating mercury to near its boiling point by contact with air, when it gradually forms minute crystalline scales of HgO. II. By heating the nitrate of mercury, HgO,NO„ till all the nitric acid is expelled. The mass is calcined Inmost to redness till it no longer evolves fumes of ^04- Thus pre pared it forms a brilliant orange red for wversl hours. The metal Is iiiih«.n„««f i- ^^ u i. — .,. , . 112 MEROURT. powder, crystallized in plates, having a density of 11*074, and is called red precipitate. III. By treating solution of corrosive sublimate, HgCl, with an excess of caustic potash also in solution. The HgO is thus precipitated as a dense powder of lemon- yellow color. This variety appears to have stronger affinities than the common red modification. Mercuric Oxide is slightly soluble in water, and the solution has an alkaline reaction to delicate color-tests ; combines with acids to form salts, many of which when soluble are decom- posed by water into an acid salt which remains in solution, and an insoluble salt which is precipitated. 390. Mhboubods Ohloridh, or Calomel, may be produced by rubbing up together in a mortar, 4 parts by weight of mercuric chloride, HgCl, and 3 parts by weight of mercury, and after- wards subliming the product. It may also be formed by sub- liming a mixture of 1 equiv. of mercuric sulphate, 1 equiv. me- tallic mercury, with one third their weight of common salt. The rapor should be collected in hot water, when it condenses into a beautiful white impalpable powder, and the hot water at the same time dissolves out any corrosive sublimate that may be carried over. Mercurous Chloride may be obtained, in four-sided prisms, by slow and careful sublimation. It is slowly decomposed by the long-continued action of light in metallic mercury and cor- rosive sublimate (Hg^Cl =z Hg + HgCl) -, is almost insoluble m water, requiring some 260,000 times its weight of water to dissolve it. 400. MiBODRio Chloride, or Corrosive Sublimate, may be ob- tained by dissolving red oxide of mercury in hydrochloric acid, or by dissolving a mixture of equal parts of mercuric sulphate and common salt. It dissolves in 16 parts cold and 3 parts boiling water, in 2} parts cold or 1^ parts boiling alcohol, or in 8 parts ether. Its aqueous solution has an acid reaction. HgCl crystallizes from solution in right rhombic prisms ; when sub- limed, it condenses in colorlesaoctahedra; forms an insoluble compound with albumen, and hence probably its antisentic MERCURY — PROB LEM8. 113 density of HgCl, with tion. The r of lemon« e stronger n. ie solution bines with re decom- ution, and oduced by f mercuric and after- id by Bub- squiv. me- salt. The condenses t water at that may d prisms, iposed by ' and oor- insoluble water to lay be ob- oric acid, sulphate I 3 parts lol, or in n. HgCl rhen sub- insoluble mtisentic power; ii not decomposed by HO.SO,, HO,NO,, or HCl, but is largely soluble in the last two. ' 401. Tm Subbdlphidb or Mibcury is prepared by precipitat- ng^y from its solution by means of sulphuretted hydrogen; it tl : t!. " "'°^''*'* ^^ *"'*' ^^**» '»«*»»'« °»«rcury and the protosu phide. Mbroubio Sulphid. may be prepared by fusing one part of sulphur in a crucible and adding by degrees 6 or 7 parts of metallic mercury with constant stirring, and coverinir LrT^'^iu* *''*" **'*'' ^^^°^"«' ^' i°«*°»«« from the heat Vermutn '*^ ^'*y»*»»i"« n»«3s thus produced is known aa brim!:^^^^''^'?'''' ^' * ^'"'^ powder,-the Proto-iodidh, a br 11 ant red powder, which is best obtained by mixing toother solutions of iodide of potassium and corrosive Sublimate! falUnl!h!r7'''7u"'''*^' "' ^" '^'' *°d 8o:unlikelyto itrtitdt::^ -'''-' '^^^ -^ -^^ -«- am*out; If' '^T^*^ "' each'^entary constituent in a given rrsTtl T '""'''^ '°"^P°"^^ "^^y ^« '^^^^ *>y th« follow- ing statement in proportion :— . .r ww Or ; If £ = the atomic weight or chemical equivalent of th* compound. e = the atomic weight or chemical equivalent of any particular constituent. W^= the weight of the compound in lbs., ozs. or grs «» = the weight of the constituent in question, in lbs., ozs. or grs. ThenjS : e :: W : w. exW And therefore w = E .^Y""* ^'"^""^ "^"^ ^^'' °^ ^"^P^"^ ^'^ there in 100 lbs. of Gyp. SOLtTTION. Gypsum = CaO,S03+ilIO. Therefore the atomic weight f ~ CVj-j-zS +2H+Q0. - "~" - - t — > - I -nj s; ou. a'hen86:16::l00:^i^=18JHbMn*. lU PBOBLIMS. Then 235*6 . m\) . Jrt : And 286S : 8SS : : 240 : Calomel la •utwhloride of mwreury = JSr^,, c/ Ato»l^ %«ight of 2 equlr. of Hg^mo.' " " 1 equiv. of C7 - aa-s. Atomic ir«l«ht of calomel OH't. 200XM0 "^aasT" "^ ^^^H^ *"• '>' 'wcury. 8 B-Bxa 40 „^,. BxAMPiH 8.-H0W many poundi of each elementary conitituent ar« there in 180 lbs. of saltpetre P SOLUTIOir. Saltpetre ia Nitnrte of Potassa = KO^On = K-\-N-{-iO, Atomic weight of 1 equiv. of Jf = 89, lequiv.ofiVs 14. 6 cqulv. of O = 46. of Saltpetre ::=101. 180X89 101 = ^Hh ^^*' 0' Potassium. 180X14 101 = 2*i*A- ^^' 0' ITltrogen. 180X48 „ .. „ ^_ = 8ft^^lba.ofOxy«en. Then 101 101 101 180 : : S9 : 180 : : 14 : 180 : : 48 : 101 EXBBOIBB. 1. Give the chemical names of the following corapounda :— HO ; CO^ ; Al^O^ ; NO^, ; C/0, ; 2C,30 ; -ffOj^O,. 2. Give the symbols of the following compounds :— Carbonic oxide ; hydrocyanic acid ; potash ; nitrate of soda ; saltpetre ; silicic acid ; gypsum ; Epsom salts ; apatite, dolqaite; permanganic acid ; defiant gas; hyarochlorio acid; calomel; cinnabar; selenite ; vermilion; red precipitate; corrosive sublimate;' hydriodic acid; cyanic acid; ammonia; bleaching powder ; carbonate of soda ; lime. 3. Calculate how much of each elementary constituent there IS in 100 oz. of each oi' tho foregoing compounds. 4. Given t'ua spec, p ofmeicury vapor 7-000 and its che- mical equivalent 100, ha.\ v. Oimb'umg volume. s ■•H' R1A0BNT8. atAreibtrt 116 ry. se. tituent art nds:— I 3' itrate of >m salts : ant gas lelenite tlimate eaching nt there its che- •7 «qui7. 37, find its combining volume. 9. Given the spec. grav. of phosphuretted hydrogen 1240 and itfi chem. equlv. 35, find its combining volume. 7. Give the chemical name and also the atomic weight of each of the following compounds :— C,N', FiO,', CaO,SO,+20', MnO,-, FeS,-, Hg,0. 8. Give the symbols and chemical equivalents of the follow- ing compounds :— Oxalic .Add; laugLmg gas; Glauber's salts; litharge; light carJuretted hydrogen; sulphuric acid; chlo-' rate of potaasa ; hydrocyanic acid; tartar emetic: red lead. 0. How many pounds of each elementary constituent are there In 260 grs. of each of the foregoing compounds? 10 Give the general formula of each of the following com- pounds :— 6 *" Protoxide ; bisulphide ; pentoxide ; teriodide ; sulphate ; carbonate; cyanide; chlorate; hyposulphite; ses- quichloride; sesquichlorate ; nitride; sulphionide; sesquicarbonate ; nitrationide ; suboxide ; binoxide ; pentisulphide ; sesqulsulphate ; binitrate. REAGENTS. Sulphuric AoiD.-Frequently rendered impure by presence of 1««h arsenic, and nitric acid. The load may be detected lyllZgZth^or eight parte of distilled water, when, IT lead be pre Jt, aSi^ssif^ro- Rita Sf ' ^^d^"ted with water, and a stream of ffS passed through 'H pUde. V her. a drop or two of soluUou of indigo in HO,SO, la Xed sent 0r'2Toj.T' *'\''°^ ''''' ^ ^«^«^« '^ '' "itrio ^i^T^re^ ^?L+? '^^' '^^ ^^ *^«*®«*«^ ^y t^e production of a brown dte- coloration on acrystal of sulphate of iron when suspended in theTuJe^ Pure ^0,503 can only be obtained by careflil dHtillation, but for ordi 7JZTr *^%«"^P^»"« »«id of commerce is sufficient pure acfdrr..1.r:l'?L^^«!1^'f-'^.-'.^»'-^^^^^ -main beWnd when the x--— v.. , z^j^wmonc aoiu, awlwiud by the tbrmation of a white 116 BSAOENT8. precipitate with nitrate of silver; and sulphuric acid, detected by diluting the acid with fire times its weight of water, and adding nitrate of barytes, when a white precipitate of sulphate of barytes js thrown down. May be purified by distilling and rejecting the first and last fourths that pass over. Htsboohlobio Acid.— Impurities, SO^; SO3; CI; Fe and Ai. The 80z is detected by chloride of barium, which gives a white precipitate of sul- phate of barytes. The SO^i is oxidized by boiling with the addition of NOn and the resulting S0» detected as above; the chlorine is detected by its bleaching a solution of indigo when added to the suspected acid ; iron, by giving a greenish black precipitate with sulphide of ammonium; arsen- ic, by precipitetion as yellow sulphide upon passing a current of HS through the acid. TxvmnABXO Agu> (CiH^0iQ-\-2H0) of commerce is suflBciently pure.— Solution, 1 part in 10 of water. Oxalic Acid (Cj O34- 3//0) of commerce is sufficiently pure. Solution, 1 part in 16 of water. AoBTio AoiD (C\HzO%-\-HO).--1he liquid acetic acid of conunerce is pure enough for most purposes, and is sufficiently strong. (May contain SOz, or more rarely SOt and HCl.) Ethbb (CiH^ O) of the shops is sufficiently pure. Alcohol (C4if6 02).— Rectified spirit has a specific gravity of 0-83, and contains 14 per cent, of water. Absolute alcohol is obtained from rectified spirit by distilling it, first from caustic lime, and afterwards from ignited carbonate of potassa or anhydrous sulphate of copper. Watbb (HO) for chemical purposes must be carefully distilled. Chlobinb Water (JT0-|-2C7).— Pass chlorine gas into distilled wafer till saturated. Must be prepared as required. SuLPHUBETTBD Hydbogbn (ITS).— Add hydrochlorfc acid to protosul- phide of iron in a gas-bottle ; wash the evolved gas. When a solution of it in water is employed, it should be freshly prepared. The solution ought not to become black on the addition of ammonia, as it will do if iron be pre- sent. Carbonatb OB- Ammonia (2NHiO,ZCOi).—T\iQ clear white masses of sesquicarbonate of the shops are chemically pure; dark colored portions must bo rejected. The salt is dissolved in 4 times its weight of cold water, and then mixed with 1 part by weight of liquid ammonia to neutralize the excess of COt. Ammonia (NH^) of commerce is pure; may be diluted with an equal bulk of water. Chlobidb of Ammonium (^ITiCO.— Dissolve the commercial salt in water, add a few drops of sulphide of ammonium, and boil till all odor is lost; when this mixture is filtered from the precipitated sulphide of iron, it consists of a solution of pure chloride of ammonium. Sulphidb of Ammonium {NH^S).—Y»»i HS into a solution of NHz till the liquid produces no precipitate with a solution of MgO,SOn. Oxalate of Ammonia (.R^J24 0,C2 03).— Exactly neutralize a solution of oxalic acid bv ammonia^ and crvstallize. The crystals may be dissolved in 24 parts of water. 1 by diluting e of barytea, wn. May be tat pass orer. U. TheSOi pitate of Biil- > addition of 1 detected by i acid ; iron, aium; araen* nrent of HS ently pure.— re. Solution, conunerce is [May contain r of 0-83, and i^om rectified from ignited lied, istilled water 3 to protOBul* ilutionof itin [on ought not f iron be pre- tite massee of [)red portions »f cold water, ueutralize the vith an equal ercial salt in till all odor is phide of iron, I solution of fMgO,SOa. ize a solution r be dissolved itBAOENa?S. 117 amon >i?*^ ^^^'^^> of commerce is very impure, containiu. •h^ i* ^'^ ^^'^ ^^ ^""^ «^^^«d fro™ the flint g ass bottles^n l^ ' T*""* *" '''P*- '^^^ commercial salt may be rendered sui dently pure ^dissolving it in absolute alcohol, in whteh its impuritte^ «e e«l^?n Of ro'^T"*' "i"**'^'^ ^^"P^"^*^ '» » «"-^ dish, ^Jh Ite^i? exej^on of COt, gives perfectly pure JfO.J^o. Preserve in German glass J,tZf «' PoTASMiTM (JT/) of commerce is sufficiently pure for most purposes, but may be separated from KO,COt by crystalLatim, frnm <^^e alcoHol. The solution for tactions' con^slstr ofTptT/I IZ CrAKiBK OF PoTASBirM (ATQ,) of the shops is Sufficiently pure l/CarX." '' ^^^^««--(^-^^^)of the Shops is p'url Dissolve fbf ZT.«''T"'' *''' ^^!i««^^^ <^3 C/.??^) of commerce is pure enough fbr analytical purposes. Dissolve in 10 parts water ««nougn Vxl^^^^'^f ?f PoTAMirM (JfW).-F«se 46 parts of K,qry + 17 ^0,C02 + 32 of *9 m a covered iron crucible; allow the fliged miis Z coo^^and then boil it in strong alcohol. The sulphocyanide c^^alto o^ cooling. Dissolve 1 part in 10 of water. «« crystallizes on ' In^ pTrt^water'*''^^''^ ^""""'^^ '^'^' '^°**' "" ^"^^'^^""^ P°^«- I>i«oIve andXori^^l/^^Xr.^^"'""^'-^"^^^^^^^^ *^^ — -^^ «^t> JdTss1J;ein^^Twrer''''^^•-^^^^^^^^ *^^ commercial salt, in^?^r:?wTter^"^"" (^0,003 ).-Dissolve the commercial salt po?ra'"° ^'''''' (^«0.^0).~Prepare in the same manner as caustio ACMATB ojf Soda (JVaO,J) of conunerce is sufficiently pure. Dissolve in 4 parts of water. Is cheaper and is used as a substitute for £0 A Gabbokatb of Soda (NaO,C02) of commerce is pure enough 'for all purposes except toxicological investigations. ^ BiBOBATB OF SoDA, boMK, (iVaO, 2BO3 + 10 J70)._Ke-crystaUi2e the commercial salt. Heat the crystals in a crucible tiU theycSeto^wei and then powder the residue. It is used only in blowpipe ex^erimeZ PHO8PHATK OF SODA (2I,aO,HO,PO, + 12 BO), thecomSS^saSt may be rendered sufficiently pure by two or th,^ w-crystallizatio^ For' tert solution, dissolve 1 part in 10 of water. ""'"anoas. For Baryta Water is a saturated solution of baryta (BaO). The barvta f« b«t ob^ned by heating to i^ness in a cnicible 6 parts of fln^y poX^ Ba0.80, + 1 part of powdered charcoal + 1^ parts of flour. The resiu «H ?r V^l^"^'^ ^*^ '"'^' ^'' " ^^'^^ ""^^ ^^ « «^k loosely coSS" „..,, „ixuv iivt TTitii cnz-ciui uACiueiou uTuHrbonio acid I 118 REAOENTS. Chloride of Barium (J3a(7/).--Se-ci78talIize the oommorcial salt anci dissolve in 10 parts of water. NiTRATK OF Baryta ( BaO,NOs ).— Re-crystallize the commercial salt and dissolve in 10 parts of water. LiMK (CaO).— The white pieces of fl-eshly burnt quicklime should be preserved in well-stoppered bottles. Chloridb of Caloitim (CaCl+HO) is prepared by dissolving the finest white marble, or precipitated carbonate of lime, or Iceland spar, in hydro- chloric acid, the acid not being in sufRoient quantity to dissolve the car- bonate of lime. SULPHATK of Limb (C4»0,»S03 -|- 2 ITO) .—Precipitate pure carbonate of lime or chloride of calcium with SO3 , and wash the precipitate till it is no longer acid. A solution is made by boiling the salt in distilled water and filtering. ScLPHATB of Magnesia {MgO,SOy + 7 J^O).— Dissolve the commer- cial salt in 10 parts of water. Irow (Fe).—The purest iron of commerce is met with as piano-forte wire. Ferrous Sulphate (Fe0,80i + 7 -ffO).— Dissolve the commercial salt in cold water. Ferric Chloride (JF'e 2 C/3).— Dissolve the purest iron inHCl, boiling the solution, and adding NOs drop by drop till the greenish-brown color of the solution changes to a bright yellow. The FaO^ is then precipitated by excess of ammonia, and the precipitate, after thorough washing with hot water, dissolved in HCl, care being taken not to use enough of the acid to dissolve all the ferric oxide. Nitrate of Cobalt ( CoO,NOs + 8 J?0).— Dissolve the commercial salt in 10 parts of water. Copper (Ctt), in the form of clippings, foil, and wire, should be pre- served in well-stoppered bottles. Sulphate of Copper (OitO,503 + 5 ITO).— Re-crystallize the commer- cial salt or dissolve pure copper (obtained by electrolysis), in hot sulphu- ric acid. Dissolve 1 part of the salt in 10 of water. AoETiTB OP Lead (P60,.4).— Re-crystallize the commercial salt, and dissolve it in 6 parts of water. Nitrate of Silver (AgO,NOs).—Fuae the pure nitrate (see Art. 887), and dissolve it in 20 parts of water. Mercurous Nitrate {Hg^ 0,JV05).— Dissolve pure mercury in cold NOs and keep the solution in a bottle over metallic mercury. Mercuric Chloride (ITfir C?) .—The commercial salt is suflloiently pure. Dissolve in 16 parts of water. Protochloride of Tin ( 6. Chlorates moistened with SO3 evolve yellow C7O4, which is very explosive. 6. Chlorates in solution added to tincture of litmus, upon the addition of a few drops of SO3 bleach the litmus. NoTB.— Test 6 and 6 are regarded as most characteristic. IODINE OR HYDRIODIC ACID. 1. Iodine is distinguished by its beautifUl violet colored vapor, its bleaching power, its solubility in alcohol, and in solutions of the alkaline iodides, its odor, the blue color it strikes with starch, &o. 2. Iodine is liberated fW>m iodides by the action of SO3. 8. Iodine is precipitated from solution of iodide as a brown powder, by the addition of chlorine or fiimiug nitric acid. 4. Iodides with AgO,N06, give a yellow precipitate insoluble in HOs andin^ffs. 6. Iodides with acetate of lead give a yellow precipitate, which dis- solves in considerable excess of water at 2l2<', and upon cooling is de- posited in golden platesi 0. Iodides in solution do not give blue color with starch till the iodine is .1 j*.i-i> - ./• i^y-k iit;«rniou uj uwuuvu ui ^V3 ur C/(, occ. I other adds Btible, a son- poured on a irater turbid. fcture of COi » precipitated HCl. ', its pungent ie precipitate lot ivitlt feul- 'hioh is very the addition >d vapor, its the alkaline I powder, by ible in H^Os , which di8< toling is de- the iodine is BEAdTiONS. BROMINE, BROHIDEg. \u 1. Free Bromine is recognized by its odor, its color, its great volatility and solubility in water, its bleaching p6wer, and the yeUow color it strikes with starch, a. Bromides, like chlorides and iodides, are soluble in water, sparingly soluble in alcohol, and very nearly insoluble in ether. Bromine is libe- rated from a bromide in solution, by the careftil addition of chlorine, It remains dissolved in the water, and may be separated from this by agita- tation with ether, which carries it to the surface. 8. Bromine, or bromides in solution, give with AgO.NOa, a faintly yel- low precipitate, insoluble in boiling iVOs, but is slowly dissolved by con. oentrated !/JEra. CYANOGEN AND CYANIDES. 1. Free cyanogen is distinguished by its odor (like that of bitter almonds), its exceedingly poisonous action on the animal economy, and its burning with a violet flame. 2. Cyanides in solution, cyanogen, or hydrocyanic acid, give with Ag 0,N06 , a white precipitate soluble in NH^ , and (slowly) in boiling NOk , but insoluble in cold NOs . The gas cyanogen may be evolved from this cyanide of silver by careiW ignitloii. 8. Cyanides are decomposed by acids, hydrocyanic acid being evolved. This has an almond odor, burns with a bl'ue flame, and is exceedingly poi- sonous. If mixed with a little NH^S, and boiled till aU odor is destroyed, and the residue treated with FetCl^, a splendid blood red color is pro- duced, owing to th© formation of ferric sulpho-oyanide. SULPHIDES. 1. Hydrosulphuric acid or sulphuretted hydrogen is recognised by its odor, its poisonous and narcotic propertieB, its solubility in water to the extent of two volumes, its burning with a blue flame, and the readiness with which it may be made to assume the liquid state by pressure or cold. Also by its precipitating most of the metals from their solutions. 2. Sulphides are, for the most part, insoluble in water; but are soluble in acids ; they are also nearly ail highly colored. 8. Sulphides, warmed with concentrated SOs or HCl, generally give off ffS, which is distinguished as above described. 4. Sulphides (insoluble) may be converted into soluble NaS, by flision with NaO.COi on charcoal. This and aU other soluble sulphides give a beautiful violet or purple color, with a dilute solution of nitroprusside of sodium. SULPHUROUS ACID AND SULPHITES. 1. Free SOt is distinguished by iU odor; solubility t© extent of 50 volumes in water; its bleaching properties; and its dsoxidisdng effect upon Iodic add, from which It liberates the iodine,— hence it blues test paper I repared by a solution of starch in iodic acid. 122 REACTIONS. 2, SulpUtes are for the most part (except those of the alkalies) insoluble in water and saline solutions, but are soluble in weak acids. 8. Sulphites heated with SO3 are decomposed with effervescence and evolution of ^Oz. 4. Sulphites boiled with stannous chloride {SnCl) and ffCt evolve B8, which may be detected by its blackening the acetate of lead paper. 5. Sulphites are decomposed by the addition of HCl, or any other strong acid; the SOg being evolved without the precipitation of sulphur. (Sul- phites are thus most easily distinguished from hyposulphites, as strong acids added to the latter evolve SO^ and precipitate sulphur.) SULPHUEIC ACID AND SULPHATES. 1. Sulphates are for the most part soluble in water; but those of barium, mercury, and lead, and a few other metals, are insoluble. 2. Sulphates fused with NaO,COi on charcoal are reduced to sulphides. 8. Sulphuric acid and sulphates do not evolve ffS when boiled with a solution of SnCl in HCl. 4. Sulphuric acid and sulphates give white precipitate with BaO.NOs or with £aCl. The precipitated BaO,80z requires 43,000 parts of water to dJMolve it; is sparingly soluble in SO3 ; and is insoluble in Nd and HCl. 6. Sulphuric acid and sulphates give white precipitates with solutions of mercuric or lead salts, and also with solutions of the salts of strontia or lime. PHOSPHOROUS ACID AND PHOSPHITES. 1. Phosphites (neutral) are, with the exception of those of the alkalies, insoluble m water ; but the acid phospites are soluble. 2. Phosphorous acid and soluble phosphites reduce silver, gold, mercu- riOM^d cupric salts, and precipitate the metal, especially upon boiling the 8. Phosphites in solution are unchanged by being boiled with caustic potassa. ^4. Phosphites (dry) heated evolve pure hydrogen; phosphite of lead, however, evolves phosphuretted hydrogen. PHOSPHORIC ACID AND PHOSPHATES. 1. Phosphates when neutral are (except those of the alkalies) insoluble in water; but many of the acid phosphates, especially those with formula MO, 2H0, POn , are soluble in water. Most all are soluble in acids. 2. Phosphates or PO5 give with CaCl a white precipitate, soluble with- out effervescence in acetic acid. 3. Phosphates or P0« give with AgO,NOs a yellow precipitate, soluble mJyrOs orinjVHa. 4. Phosphates or POs agitated with NH^Cl; NH3, or MgO.SOs, ^ye a crystalline precipitate soluble in acetic and other acids. 5. Phosphates or POs (the former upon the addition of HCl or NOs ) give a yellow precipitate with molybdate of ammonia. The precipitate msj aot fo*x« iuuuediwtoiy, but wiU ao so upon standing for ^ short tiwe. BEAOTIONS. 123 es) insoluble escenoe and I evolve HS, >aper. Dtber strong phur. (Sul- B, as strong e of barium, sulphides, oiled with a iaO,NOs or of water to >5 and HCl. solutions of ' strontia or he alkalies, }Id, merou- boiling the rith oaustio te of lead, insoluble ith formula cids. luble with- ite, soluble KSO3, give 1 or NO5,) precipitate iUovt tiWQ. SILICIC ACID. 1. Silicic acid in powder dissolves as an alkaline silicate when boiled with excess of NaO or NaO,COi. 2. Silicates in solution are decomposed by many acids, as HCl and the silicic add precipitated. If now this precipitated SiO^ be removed and dissolved in dilute HCl, and dried perfectly in a water bath, anhydrous SiOa remains as a white insoluble gritty powder. BORACIC ACID. 1. Borates in concentrated solution are decomposed by SO3, the boraoio acid crystallizing in plates when the solution cools. 2. Boracic acid imparts a green color to the flame of alcohol. If a bo- rate Is employed, the addition of SO^ is necessary in order to set free the BO3. 8. Boracic acid acts like an alkali upon turmeric paper; i.e., turns it reddish brown. To apply to test, dissolve the suspected berate in excess of HCl, and apply the test paper. POTASSIUM. (Solution for reactions, JKCl in water.) 1. Salts of K when pure tinge th0 flame of the blowpipe violet. 2. Salts of K are readily soluble in water, with the exception of the bitartrate and chloroplatinate. 8. Salts of K in rather concentrated solution give, when agitated with solution of tartaric acid, a white crystalline precipitate of cream of tartar, soluble in 80 of water. 4. Salts of JTin solution, slightly acidulated with HCl, give with a mix- ture of PtClt + HCl a yellow crystalline precipitate of chloroplatinate, insoluble in alcohol, but soluble in 144 parts of water. SODIUM. (Solution for reactions, NaCl in water.) 1. Salts of Na tinge the blowpipe flame yellow. (Only reliable test.) 2. Salts of N^a are all soluble, except the acid metantimoniate, which is obtained by adding a freshly prepared solution of metantimoniate of po- tassa to a solution of a soda salt. This test is difficult of application, and not much used. « CALCIUM. (Solution for reactions, Cad in water). 1. Salts of Ca color the flame of a blowpipe red. If a trace of soda be present, the flame wiU be colored orange, 2. Salts of Cd heated on charcoal before the blowpipe becomes remark- ably incandescent. 3. Salts of Ca in concentrated solution are not precipitated by CaO,S03, but are partially precipitated by dilute ^03 or by BoiuHon of KO.SOi. The precipitated CaO,S03 is soluble in 460 parts of water; the solution giving a precipitate of oxalate of lime upon addition of oxalic acid, and of BaO,S03 on addition of £aCl. 4. Salts of Ca are precipitated by solution of C2O3 or of NHiO,Ci03. The preeipitated CaG,CiGi is soluble in HCl, but is iusolubld in acetlo acid. 124 HEAOTIOMS. 1I-K.1V6 It. I, iSnbl. f„^" ' ''"'"' "'"^ *" »' «"" "•<•' •» STROHHIIM. (SolutiOB tor „.ott„.,, 8r0.1f0, 1. wl.,.) Th. I'iJl^f \"! Preolpltnted by SBlphnilo add or by roloWe mlphttM ^0 ."Kta z^z" '"'"'"° *" «^ ™" "' '" »^ «•»« "Sjr^ BARIUM. (Solution for reaotioiw, BaCt in water.) I. SaJteoJ^«Zrr \^f°^^*'-«''««^«°«e to the blowpipe flame. Of C^O^o! Z ''^.*' precipitate with dilute SO,, or with solution ^i^i^^^^h;^-^^^^^^^ ^ P-«-"- P'-^PH-ta. e. salts of barium are precipitated by hyposulpWte of soda. aUGNESIUM. (Solution for reactions, MgCl In water.) jnitJ.*^*'"^^^*"*' ''''* precipitated by solutions of sulphates or chh). taL,^*f i!!f ^^ fl\'' ^T^^^^ ^^«" boUed with ferrooyanlde of po- tassimntho precipitate being insoluble in ^ff.Cl but soluble in ffCl. ble'in«l?« ^f^^'^'^P"**^^5^^<^'^^^'*^»® precipitate being solu- ble in solutions of salts of ammonia. * 4. Saltsof 3ffl» give a white crystalline precipitate with soluble phos. phates on addition of a little NS. wmpie pups. ALUMINUM. (Solution for reactions, Ah Ch in water.) o/thrit^ ^ ^^^ '^"^ *'*°*"° ^^ * ^"*® precipitate soluble in exdess Ji^^^^y^ give with NH, a white precipitate, nearly insoluble in excess of the precipitant. .^ v*m ^L^^^.Z^ it t; "°V°^°' *^« ^^°^PiP« flame; but when intensely IJ^. ?f ^^^.^^^'^P^P^'*^' ^^''''i ^^"^ moistened with nitrotTof cobalt, they acquire a fine blue color. «"™w o? ••"^ f potaMiiun >ld water to Uioio HoMbi, ter.) isily difltin* lilloic add, > Bulphates, g water: to flame, th soIutioD dissolve it, X reoipitate, latea, ox^ lydroflvo* ) I or chro- ide of po> HCl. ling Bolu* ble plios* ) inexigeM loluble In [Qteuselj litrate o|' BEA0TI0N8. 125 Zmc. (SoluUon for reaotloM, ZnO,SO^ In water.) ^^^^:i^^^^7r^:r:'Z^^ of «oda«e Educed, i. yellow wZrhorbutThrSh^'::^ 1t:"*.f cna.coa^..U.i ^n:^T:.^:Z^:^:il^'£^ ^ -^"° P-^P^-te of b^drate of "*'"■"'■>'. (Solntlon for w,oUoii.,Ci,o,jro, In water.) COPPEB. (Solotloa for reaoUoM, C%o,SO, in water ) S'CntfiTTj?''.'''' ''?'''*''•'''»''''''''''"''• ''»''»«'>^M«wC ooid. Jiixpoeed to the inner flame this elaM either Imam ifii ««i«, « v r"r.r '""' °^"^" '^' "-"*"? " '^^"X Of Cr ^bls; 3. Salts of D^iL orlvA nrUK C/'t .11-1..^.. df»rl.-brownwl,enh;at'edr ""'""'^"^ "«^ '^^^^^i'"*^' ^^•«t' ^e^omes •• -4 126 RIA0TION8. 4. 8alt« of Cu give, with JSTHi, a greoBlsh-blue preoipitato, wbloli in- stantly diMolvM in exoeta, forming a splendid blue or pnrple solution. 6. Salts of Cu, with fl»rrooyanide of K, give a olaret-red precipitate, which is insoluble in adds, but readily soluble in NH9, and is decomposed by KO. This, the most delicate test for copper, is capable of detecting one part of copper in 1,000,000 of water (Sarzeau). 6. Salts of Ou, in acid solution, coat a polished steel needle with metallic copper. MANGANESE. (Solution fbr reactions, MnO.aO^ in water.) 1. Salts of Mn, fhsed with a borax bead in the outer blowpipe flame, yield a violet red glass; the color gradually ftides in the inner flame, and ultimately disappears. 2. Salts of Mn, on platinum wire with carbonate of soda, when heated in the outer flame of the blowpipe give green mass of manganate of «oda. 8. Salts of Mn, with caustic KO, or with NH^, give white preoipiates, insoluble in excess, quiclKly becoming brown. 4. Salts of if n in acid solution give no precipitate with HS, but give an insoluble flesh-colored or buff precipitate with NH^^S. The precipitate turns brown on exposure, and is insoluble in acids. IRON (solutions for reactions FeO,SOi, and FetCh, in water). 1. Salts otFe, flised with a borax bead in outer flame of blowpipe, yield a brownish-red glass, which assumes a bottle-green color in the inner flame. 2. Salts of -PeO give, with caustic alkaUes and with NHi, nearly white precipitates, insoluble in excess, which rapidly change in color to greenish and ultimately reddish-brown. 8. Salts of FeO give a black precipitate with NHiS. The precipitate is soluble in dilute acids. HS gives no precipitate in aqueous solutions of ferrous salts. 4. Salts of FeO, treated with ferrocyanide of K, give a bluish-white pre- cipitate which rapidly becomes darker, forming Prussian blue. Ferri- oyanide of JT gives a deep blue precipitate at once with salts of J^'eO. 5. Salts of FeO, treated with sulphocyanide of K, give no precipitate or change of color if the salt Is pure. If any Fet O3 be present, a red color is at once produced. 6. Salts of Fe%Oz, treated with caustic alkalies or ammonia, give a red- brown precipitate of hydratod sesquioxide, insoluble in excess. 7. Salts of -Peg O3 , treated with HS, give a nearly white precipitate of sul- phur, the i^cgOa being reduced to FeO. Sulphide of ammonium gives a black precipitate. 8. Salts of Fe'i O3 give a blue precipitate with ferrocyanide of K, but give no precipitate with ferrioyanide of JT. 9. Salts of Fez O3 strike a deep blood-red color with sulphocyanide of JT, the color disappearing on addition otHgCl. LEAD (solution fbr reactions PbO,NOs in water). 1. Salts of Pb, flised with NaO,C02 in the inner flame of the blowpipe, give a malleable button of lead, and color the charcoal around the outer %9sm Witb a yellow inonutatioa of PbO, REAOTIONS. 127 a. Salti of Pb give, when trotted with oaunUo alkahes, a white preoiDl- tate inaoluble in exoeM. 8. Salt, of Pb, with carbonates of KO, NaO, or NH^O, give insolable white prooipitates. 4. Salts of Pb, with 80^, give white precipitate insoluble in JVO4 ft. Salts of Pb, with JVif 4 5 or with HS, give black precipitate. 6. Salts of Pb give a bright yellow precipitate with Kl, soluble in larire excess of boiling water. 7. Salts of Pb, with chromate of potassa, give yellow precipitate soluble in potassa. TIN (solutions for reactions 9nCl and SnCh in water). 1. Salts otSn ftised on charcoal with cyanide of ^in the inner blowpipe flame, give white maUeable globules of metalUo tin. and a liffht whit« Incrustation. * 2. Salts of »nO treated with KO or with NH^ give white precipitate soluble in excess of potassa. By boiling this concentrated solution the tin is partly precipitated in metallic state a^d partly converted into anO%. 8. Salts of SnO in acid solution give a black preoipiUte with Jiff^S or 4. Salts of ,SnO treated with HgCl give white precipitate of HgtCl, which, after a time, if buffloient SnCl be present, is converted into a grey precipitate of metalUo mercury, 5. Salts of SnOa treated with KO otNHs give white precipitate soluble In excess of JTO. 8. Salts of 5n08 treated with HS give bright yellow precipitate which is insoluble In dilute SO3 or ffCl, but soluble in KO, alkaline sulphides or boiling ffCl. Both this and the p;oto8ulphide are converted by If^o^ into insoluble binoxlde. CHROMIUM (solution forreactlonsa) ^0,003, and(2) OjCTa, In water.) 1. Salts of OOj are all yellow, red, or reddish brown, 2, Salts of OrOa in acid solution are reducible by H8, the sulphur being precipitated and the solution changing in color from yellow or red to green. 8. Salts of OO3 are reduced to the green sesqulchloride of chromium by heating with HCl and alcohol. 4. Salts of OO3 in solution are precipitated yellow by acetate of lead. 5. Salts of OrOz heated with sulphuric acid and dry JVaC/ evolve dark red Aimes. 6. Salts of O2 O3 impart to a bead of borax an emerald-green color in the outer blowpipe flame, and a yeUowish-green color in the inner blow- pipe flame. 7. Salts of OTiO^ give with IfJIa a greenish precipitate but slightly •oluble in excess, the resulting />inA; solution being precipitated by boiling. 8. Salts of OjOa give with KO a green precipitate readily soluble in ©xoess, the resuiting green solution t>elng precipitated by hojling. 128 RIAOTIONI. iJISMUTH. (Solution tor roMtJoni, BiOtfiXOs in inttei-.) 1. Halts of m on obarooftl with oarbonato of voda yield in tho reducing blowplpo flam« a globule of metallic blamuth, and color the •urrounding charcoal with an inoruBtatlon of yoUow BiOj. 2. Salts of m treated with JIS give a black precipitate. 8. Suit* of Bi are deoomposod by a large exoora of water, a white baaio salt being thrown down, which is insoluble in water or in tartaric aoid. ANTIMONY. (Solutions tor reactions, SftCfa In water aoidfllated with HCl, and KO,SbOs in water. 1. Salts of Sb tosod with carbonate of soda on oharooal In tho reducing flame yield a globule of metal which is very brittle, and may bo easily rubbed down to a black powder. If continued in tho flame the glcTbule volatilizes, and the charcoal becomes extensively coated with a tvWtb 1n< orustation. 2. Salts of Sb treated with KO or NHa give a white precipitate, soluble lii excess of KO. 8. Salts of Sb in neutral solutions are decomposed by excess of water, the basic salt which is precipitated being soluble in tartaric aoid. 4. Salts of Sb treated with HS give an orange-red precipitate insoluble in dilute acids, and nearly so in Ntti and 2NH4, OfiCO^ ; soluble in eon- oentrated HCl, in KO, and in alkaline sulphides. 6. Salts of Sb in aoid solutions, boiled with copper foil, coat the latter with a grey deposit of metallic antimony. 6. Salts of Sb in aoid solutions (not containing NOs) give witt metallio zinc a pulverulent deposit of metallio antimony. /|: 7. Salts of Sb introduced into a mixture of zlno and dilute SOs prO'dttoiB an evolution of SbHi, in which the following properties ai;e tp be ob- served:— , ;,,',.; I. It bums with a greenisbrblue flame and evolves white fiunes. II. It imparts a black velvety spot to a piece of white porcelain held in the flame. III. If passed through a narrow glass tube fa«M»d at one spot to red- ness, it deposits a black metallic mirror immediately beyond the heated point. 8. Salts of SbOs treated with HS give no precipitate unless an excess of HCl bo present, in which case an orange-red pentaHBulphide is preo^itated. It behaves similarly to SbS^. 9. Salts of Sb06 give no precipitate with KO or with 2NHi OfiCOt . ARSENIC. (Solutions for reactions, AtO^ and AaOs in water.) 1. fialts of A$ heated to redness on obarcoal in reducing flame emit a garlic odor. 2. Salts of Ab give no precipitate with KO or with NH^. 8. Salts of AaOa In Add solutions treated with HS give a bright yellow precipitate which is insoluble in cold dilute acids, but soluble readily in hot RKA0TION8. 190 Snlf I'^O rS'^l.t'''' ^'•;u ' '" * '^"" *"^ -"" • mixture Of if rv ano«tedlnatnbowlthcharoo«Und JVu.., v, yields a nn^ of motalHo arBonlo. ^ < ^* yiumn » 01 Miver i> held in iolution by the ft-eo .VO ; when JV^//, ia careftillv add. ItherTjTZ*'*',^ *''°^ •^°""' "'^'"^ ^ easily B^lubfe^^^xc'eLo eltner J\rOa or J\r/r3. (Hume'fltest.) «*vo«i wi 6 Solutioiui of ^,03 with CUO.SO, and ivr^, in the same way Rive, a yellowish green precipitate, soluble roadUy in NH, or any acid (sfhed * of'^^oTdLlf^un"''''^ "f'^ '"«" ''''''' of concentrated solution . '. u "®** '^^^'^ granulated rino, evolves AsH^. which mav ho «! 1 t ^!^l^° *° hydrochloric solution, boiled with clean copper coats th« ^A«1^* w'T^ ^"^ °' "*«**^"^ ''"«"*<' (Reinsch'stesM J; ;f I w. '°*'^°d"««<* Into a «»«ture of Zn and ^Oa evo ve. ^*jy, which exhibits the following properties:- (Marsh's test? "' I. It bums with a light blue flame, and evolves dense white fumes TTT i t"* * '*"'' '*•*'* ""^^" *<» *»>»* produced by Sbm. fiircl! *''"* ' ""f **'"" "^"°' ^° • narrowglass tube under the same circumstances as already described in the case of antimony butTo mirror is rather more remote from the most heated^iT ibL'rn7lh;L:S::ir'^*'''^"^^^^^^ *- *^"* of .ntlmonybythe solves it. but does not act upon the spot of antimony. II. A drop of solution of iodate of potasw acts in a similar manner m. A drop of ^0« is placed on the spot and oarefUUy evaporated to dry- ^J fft«/^»'-d«adrop of solution ot A90,N0, i, placed onft, when if the spot were arsenic there is produced a briok-red colora^ tion of arsenate of silver, but if it were antimony no chan«) of color is noticeable. ' "uwj^ oi The armnio mirror is distinguished i^om that of antimony by the foL i owing means : ^ j ^^ IV. The tube oontalning the mirror i. heated. If arsenical, a garlic odor is perceptible ; if antimony, there is no odor. ''^'!!^' °^'*'^'*® '"^''^ *•* produced by heating the mirror and which are deposited on the sides of the tube, are examined by a microscope. AaO^ orystalUzes in octohedra, SbO^ generally in elongated prifflns. but sometime, in octohedra. VI. The crystals are dissolved in a small quantity of water and Hume's or Scheel's test applied. VII. The mirror H treated in the same manner as is described in in fo* me spotSi 130 Abactions. Vllf . The tube containing the mirror is sealed below and plunged into fth oil-bath at a temperature of about 500° F. If arsenic it is volatil- ized, but if antimony it remains unchanged. IX. The tube is gently heated, and dry HS passed through it, when if the mirror be arsenic it turns yellow, if antimony it turns orange red. A stream of gaseoous HCl is now passed through the tube, when if sulphide of arsenic it remains unaltered, but if it be sulphide of antimony it disappears. 10. Arsenic acid may be dedected by the foregoing reduction-test (4), Reinsch'8 test (6) and Marsh's test (9) . 11. Arsenic acid treated with /ra does not gire a precipitate except in acid solutions and then not readily. It is commonly reduced to AaOa by the action of SOz and then precipitated aaAaS^. ^ 12. Arsenic acid gives a brick-red precipitate of arsenate of silver when treated with AgO,NOs. This precipitate is readily soluble in NO a and NHi. SILVER (solution for reaction AgO,NOii in water). 1. Salts of Ag heated on charcoal with NaO,COt give a globule of white malleable metal without any incrustation on the charcoal. 1. Salts oiAg give with KO or with NH^ a brown precipitate insoluble in KO, but readily soluble in NH^ . 8. Salts of Ag treated with HCl give a white precipitate of AgCl, which becomes violet when exposed to the light. It is soluble in NHi, but insoluble in water and in NOa . 4. Salts of Ag treated with HS give a black precipitate soluble in boiling iVOs— with deposition of sulphur. GOLD (solution for reaction Au^ Ch in water). 1. Salts ofgold in concentrated solution give reddish-yellow pre«ipitato with KO or NIF3 . 2. Salts of Au with HS give a black precipitate Insoluble in 5O3, in HCl, and in NOs, bui soluble in a mixture of ^Os and HCl. 8. Salts of Au boiled with C2O3 give a precipitation of brilliant metallic gold on the sides of the test-tube. 4. Salts of Au treated with FeO,SOi give a fine brown precipitate of metallic gold. The supernant liquid has a blue color. 6. Salts of Au give a purple-red precipitate or coloration when treated with SnCl containing a trace of SnCh. PLATmUM (solution for reaction PtCl^ in water). 1. Salts of platinum in rathei concentrated solution accidulatcd with HCl give with KO or NH3 a yellow crystalline precipitate soluble in excess. 2. Salts of Ft with SnCl give a deep red-brown coloration. 8. Salts of Pt with KIgiye a nearly black coloration. MERCURY (solutions for reactions HgtO,N05, and Hga, in water). 1. A salt of m AmnvV' h Aa«'A/1 to > —1- ■»-- 'Hii '-1'- •■ > i! ... ary JXao^cot yields « gr«y ring of minute globulei of netnUlo mwoury. ilEAOTlONS. 131 bto in S:^'^^" '"•*^* '^"' '^'^™ • •"™«»« aoarW precipitate, solo- white to XwMd^"* *'" ^^ «""' • P"'^P"«'= wUch p««», fh,^ Iv mL* Wint; /.■;;'' ™oce»ively orange, bro™i,h.red, .nd jDal- ■ji Aiar'i.;?!. APPENDIX 1. -'("■'Iff ^••f'f v'' •• Iv. readii^g continental and certain English work« on Chemfatry, the junior student is apt to be somewhat confused by the notation adopted, in consequence of the fiict that many chennists employ the atomic weights of Gerhardt. In this system the chemical equivalents of oxygen, sulphur, selenium, tellurium, and carbon, are doubled; the others being the same as those commonly employed. Moreover, adopting the binary theory of compounds in the most extended sense of the term. It is assumed that radicals are not truly represented as regards their molecular arrange- ment when written as CI, or Cy, or H, their constitution being in reality that of a true salt or binary compound. Hence the body commonly called chlorine is regarded as chloride of chlorine, and is written ClCl; that cidled cyanogen is in fact cyanide of cyanogen, and is written CyC^/ similarly hydrogen is HH; oxygen 00; sulphur SSi &o. It appears ttom this that double deoon^positions are much more frequently n^^ with than was far> merly supposed. Thus, when oxygen combines with hydrogen to fonn water, the reaction is expressed as follows:— HH -{■ 00 = HO + HO. Many arguments are advanced in favor of this theory, one of the strong- est being that it, in a manner, explains why the affinities of bodies are so much exalted by the nascent state, as it is very forcibly urged that since the radical has not yet united with itself to form a twin atom its combining tendency is therefore still wholly unsatisfied. The following examples of this notation will render these points plain : Ordinary notation. CI HCl KCl HO,NOs CsNorCy KCy KO,CyO KGySi H HO KO,HO KO Gorhardt's notation. ClCl HCl KCl HNOz CNCN or CyCy KCy KCyO KCyS HH HiO KHO K»0 Ordinary notation. CIO KOCIO HS KS HO.SOa KO,SOz-\.HO,80i K0,80z NHa PHz 8H0,P0s K0,2H0,P0s Gerhardt'8 notation. ChO KCIO ms KiS Hi 80 4. KHSO4, KiS04, H3P H3POA KH»P04 i'Mtm-'m ni itolJ t>tr ■ ■■ troistry, the on adopted, tbfi Atomic of oxygeu, >ther8 being i the binary : ia asBnmed lar arrange- g in reality lonly called thatcidled t; BinUlarly >m this that «n was for- ten to form 'the strong* odies are so I that since I combining ints plain: rdt's ion. O O ? ? ?04 SO4. IO4, p IP04 -^0^4 Al^PKNDiX. 133 APPENDIX II. Infdrmation is often sotight by begimiore in Chemistry as to the nature and cost of the apparatus r^nired for snch simple experimentewle^ ^y find necessary for the illustration of the subject. The folt.^^! hs* will be found tocontainaU that is really essentii; but It mrt^bo™« in mind that the Stadent. by a little ingenuity, can make very muc^ oSe apparatus for himself. The cost is given as nearly as It ^n.^dT *t't ,f?!l ^'*^""**^ -ith regard'^to makingTnd ^siig chomc^ Zt «t«« will be found in WUliams' CkenHcal MalipulatiJ, TZ^XX Swm "" ^^^'y '*»<»«"*'• ^-«'».««i which can behatf^UcoIJof LIST OP APPARATUS. ASphitLamp, Betort Stand,.... '.'.'.'.'.'.'.','. •••«>« say, jjo.fio;- 2d©a.a88ortedTestTubes,!!!!!!..!!!!!!!l.*]' '*, ^'^ A ibw Florence Flasks or small Betorte,....*.' „ 3' J? A ftw Porcelain Dishes and Capsules '"" „ J"^'* A Ibw Watch Glasses, '"•■ ,. ^-^ A Test Tube Stand, '.'.'.'.'.'.'.'.'. ^" ^'^ WireTrianjfles to support crucibles,. ..'.'.*!.*.'.'.*.'[.'.'.'.''" (Can be mad© Wu^Eingd covered with cloth to support hot retorts * P^ *te Student A Pneumatic Trough can be made out of a pail ' 2 lbs. Quill Glass Tubing „«^ -.^ 2 lbs. large Glass Tubing, -cortsay, $loo IgroSsCofts, ].';."" • " 0.76 Seteralpie«tes Vulcanized Iniaiubiir'Tubing' .7'! « ?1? 1 Nest Fs6lan Crucibles, ........"" u A few Beakers or ordinary Tumblers, « ^'^ A few Predpitating Jars or ordinary Wine Glsiaees « 2 pint, 2 quart, and 2 half-gaUon wide-mouth Glass Jars, with ground-glass stoppers, for collecting gases, ' « t no 6 Quart Bottles, with ground-glass stoppers, for acids and liquids, ??*^ <*»• >^'!^'t 0.05 i oz. Iodine -. • •*t.wtli' vsl^f I' " 0.25 i 02. Nitrate of Silver (crystallized). .V..:.l ...,>!>,! ^",,,. 1,00 8 oz. Chloride AmmoiHum,. .,..^,^^,^,,i,^:-^„; . " 0.20 4oz. Cartonate Potash ....-..M^.^««^f:-i.«..-«^,« .'^: n^040 8oz. Carbonate Soda, '^^f. tsj • «»w.t ^. t.a t- 4 OZ. Acetate Lead,. ....... u ii in 4 OZ. Bichromate Potassa, , «« 0Tl5 4 oz. Ferrocyanido of Potassium ; ,'.*.',,... 7^ •• 0.20 loz.Indigo, ,.»,............, •• 0.10 i lb. Copper clippings, <« 0.06 4 oz. Nitrate Potassa, .« o.lO 1 oz. Iodide Potassium, <« 0.40 1 oz. Corrosive Sublimate, " o.lO 1 lb. Metallic Mercury, «« l.OO 4 oz. Snlpbatc Iron, *.!.!.....! '• . 06 A little fiijae, «< 2 oz. Tartaric Acid, <« o.lO 1 oz. Caustic Potaah, ., u o.lO 3 oz. Cauetic Soda, , , «« 0,10 2 oz. Chloride Barium, «< 0.15 2 03. Borax, « o.lO loz. Alum, i , < 0.10 II 0.05 l< 0.10 ;< 0.40 :i 0.10 11 1.00 It f 0.05 f • • • • 0.10 f- 0.10 1 0.10 1 0.15 4 0.10 1 0.05 < 0.05 < 0.20 < 0.25 ( 0.25 APPENDJX. 135 7. Wmianis's Chemical ManlpulaaoM, pp. 580. 8. Otto on the Detection of PolBong, pp. 178. 9. PameU'8 Chemical Analysis, pp. 620. 10. I^enins' Analytical Chemistry, 2 vols., pp. 990. 11. Odling'8 Course of Practical Chemistry. 12. Noad's Chemical Manipulations, pp. 867. 18. Bowman's Practical Chemistry, pp. 808. 14. Lehman's Physiological Chemistry, 2 vols., pp. U95 16. Bowman's Medical Chemistry, pp. 288 16. Knapp's Chemical Technology, pp. 936. 17. Kane's Elements of Chemistry, pp. 704. 18. Solly's Syllabus of Chemistry, pp. 198. 19. Leibig's Animal Chemistry, pp. 173. 20. Leibig's Agricultural Chemistry, pp. 400. 21. Johnston's Lectures on Agricultural CHemistry, pp. 707. The general student will be best served by Nos. 1. 8, 4. 5, 8, 7, and 16 ot the above-named works. THE END. ■y, pp> 852. Practical * ■».j