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Original capias in printad papar covars ara filmad baginning with tha front covar and anding on tha last paga with a printad or illustratad impraa- sion, or tha bacic covar whan appropriata. All othar original copies ara filmad baginning on tha first paga with a printad or illustratad Impraa- sion. and anding on tha iaat paga with a printad or illuatratad imprassion. L'axamplaira fiimA fut raproduit grioa A la g4n4roaiti da: MctropoliiMi Toronto Library SBiMMwft TmIuibIimv DuMrtniMit Las imagas suivantas ont At* raproduitas avac Is plus grand soin. compta tanu da la condition at do la nattatA da I'aKamplaira film*, at an conformitA avac las conditions du contrst da filmaga. Las axamplairaa originaux dont la couvartura mn papiar ast ImprimAa sont filmAs sn commandant par la pramiar plat at an tarminant salt psr la darnlAra paga qui comporta una amprainta d'imprassion ou d'illustration, soit par la sscond plat, salon la cas. Tous las autras axamplairas originaux sont filmAs an commandant par la pramiAra paga qui comporta una amprainta d'impraasion ou d'illustration at an tarminant par la darnlAra paga qui comporta una taila amprainta. Tha Iaat racordad f rama on aach microflcha shall contain tha symbol — i^ (moaning "CON- TliVUED"). or tha symbol ▼ (moaning "END"), whichavar appiias. Un daa symboias suhrants apparattra sur la darnlAra imaga da chaqua microfiche, salon la cas: la symbols -^ signifia "A SUIVRE". la symbols ▼ signifia "FIN". Maps, platas, charts, stc. may ba filmad at diffarant raduction ratios. Thoea too large 'o ba antiraly included in one exposure ara filmed beginning in the upper left hand corner, left to right and top to bottom, as many frames ss rsquired. The following diagrams illustrate the method: Lea cartas, pisnches. tableaux, etc., peuvent Atre fiimAs A des taux da rAduction diff Arents. Lorsque le document est trop grsrid pour Atrs reproduit en un soul clichA, il est filmA A partir da I'angia supArieur gauche, de gauche A droite. et de haut en bas. en prenant le nombre d'imagas nAcessaire. lies diagrammes suivants iilustrsnt la mAthode. 1 2 3 32X 1 2 3 4 5 6 CHI SHO BY THE SAME AUTHOR, AD IIJ PREPARATION, PHYSICS, STATICS, AND HYlJROSTATICS, Covering the ground which High School Pupils will be required to know for Te. chers' Second and Third Class Certificates. R« Tayo CHEMISTRY FOR HIGH SCHOOLS, OONSISTINO OF A SERIES OF CONCISE DEFiNITIONS, SHORT NOTES, AND CHEMICAL PROBLEMS. ALSO, THE ELEMENTS OF CHEMICAL ANALYSIS, ADAPTED FOR THE PREPARATION OF CANDIDATES FOR THE TEACHERS' EXAMINATIONS OF THB rics, required EDUCATION DEPARTMENT, ONTARIO. »r A. P. XNTC»HT, M.A, MtOrOB AND SUIINOB MASTIK, aOy««OUTB IVmTltmm, KtHWTOIf, OMTARIO. To whMh are appendtd Ecuamination Queationa in Chemiitry teleeted from (hn* rtetnUy itt at Toronto, Qtteen'8, and Victoria Vnivtrritiu: oho, ihos$ far Teachers' Certifieatea, /Tom 1879 to'l88U. FOURTH EDITION.: ) t • 1 , 1 TORONTO: OOPP, OLARK & 00., 9 FRONT STREET WEST 1884. * «1 6i<&^t>^ •#** MAY 8 1923 • ••• • • •• T J PREFACE TO THE FOURTH EDITION. Little new matter has been inserted in this edition, but to enable teachers and students to form a correct idea of the improved character of examination questions ^ in Chemistry, in recent years, the pass papers in arts of Toronto and Queen's Universities, for 1882 and 1883, have been added to those published with previous edi- tions of the book. Those set at the Teachers' Examina- tions in July last are also given, and for a similar reason. A. P, K. KiNOSTOV, November, 1884, PREFACE TO THE THIRD EDITION. If an intelligent business man were asked to take charge of our educational system, probably the first thing he would do would be to divide the work of secondary education c'^onr;::.*) four distinct classes of High Schools, somewhat as follows : — I. —Classical Schools, whose chief object should be preparing for Matriculation in Arts, Law, or Medicine. II. — Normal Schools, one in each county, whose work should consist in giving to second and third class teachers their literary and professional education. The training of first class teachers should be done in our Universities. III.- -Technical Schools, whose object should be the training of boys and young men for the various trades, and for mercantile life. IV. — ^Agricnltufal Schools, whose special aim should be to furnish instruction in all those sciences having a direct and practical bearing od farming Immediately after this re- distribution of the work of secondary education, should follow the abolition of Mechanics' Institutes. As institutions for imparting technical education they have been, and are, complete failures ; and the public grant now frittered away in eking out their struggling existence, might far better be spent in establishing a new class of High Schools to do PREFACE TO THE THIRD EDITION. UTION. red to take le first thing 3f secondary Ligh Schools, ect should be rts, Law, or jr, whose work md third class aal education, ihould be done should be the >r the various ial aim should hose sciences ig on fanning the work of abolition of >r imparting re, complete red away in Gtr better be iohools to do the work which these Institutes have never done, and never will do. The professions are all very much over- crowded, and therefore no special plea need here be urged for maintaining Classical and Normal Schools. But nearly 3,000 of our High School pupils leave every year to engage in mercantile, agricultural, and other pursuits, and what special training, it may be asked, has the Education- Department provided for these? Scarcely any. "Our Mechanics' Institutes," I quote from the last report of the Minister of Education, " are only circulating libra- ries." Not quite ^,000, of the Government grant of $25,000, are spent in providing practical instruction for those engaged in mechanical employment or manufac- tures ; and, in 1882, only 15 out of over 100 Institutes had technical classes at all. Skilled labor is one of the great wants of our country, and yet it seems to have been assumed by those who shaped our educational policy that no special training was needed by those intending to become artisans. There is, of course, an Agricultural College at Guelph, and a School of Practical Science at Toronto, but no one pretends to say that these institu- tions afford anything like general facilities for the acquisition of an education in agriculture or technology. To say that a classical training in our High Schools, followed by a college course in Arts, is the best prepara- tion for business or for agriculture is simply to talk nonsense. Experience has shewn that in this country few university graduates go into business and fewer still into farming. " The elementary rules 'of the farmer's art are the simplest, and the rude practices of it the easiest; yet. between the worst agriculture and the best lie agri- ..cultural chemistry, ^he application of machinery, the- laws of the economy of force, and the most curiou» Tl PREFACE TO THE THIRD EDITION. «' n V' f- problems of physiology." ♦ ♦ * ♦ * "Until the forces of nature in this land are conquered to man's use, the study of science in its various branches is an indis- pensable necessity. History, poetry, music, logic, moral philosophy, classical literature, are excellent as ornament ; but as they must, in the present stage of our country's development, occupy th-^ leisure part of life, so they ■should occupy the leisure part of education." There is no good reason why secondary schools specially designed to teach science and technology should not be successful. Until county Model Schools were established throughout Ontario and proved success- ful, it was supposed that no instruction in pedagogy could be had outside of the Toronto and Ottawa Nomal Schools. And until schools for the teaching of science, technology, and commerce are in successful operation in ■every city ; and, others for the teaching of agriculture in every district, there will always be cranks and croakers who will insist that no education worth the name can be had outside of the four walls of a university. The Ger- man professors have not yet settled the case of Science vs. Classics. A higher court must pioncunce the final decision. Notwithstanding complaints that too many subjects were taught in our schools, the whip of public opinion lias of late years compelled the addition of one modern subject after another, until at present there are some twenty-five optional or 'obligatory ones on the High School programme. Add to this the fact that under existing regulations each school is expected to prepare for Matriculation in Arts, Law or Medicine, for at least three grades of teachers' certificates, for admission to the Mili- tary Oollege,for the Civil Service examinations, and lastly ior Agriculture, and we have a state of affairB that might )N. PREFACE TQ THE THIRD EDITION. Vll "Until the to man's use, es is an indis- 0, logic, moral as ornament ; our country's life, so they >> dary schools technology lilodel Schools roved suocess- t in pedagogy Ottawa Nomal ing of science, ul operation in agriculture in IS and croakers » name can be ty. The Ger- sase of Science unce the final many subjects public opinion of one modern here are some on the High <:t that under I to prepare for r at least three on to the Mili- ions, and lastly lira that might well appal any head master, even an Arnold. Amidst this terrible jumble of * subjects and aims — " confusion confounded" — two or three teachers, in eacli worse school, bravely struggle to carry out the Departmental regulations, and especially to prepare their pupils to run the gauntlet of the examinations — honestly if possible, but through them at any cost. If our High Schools are to contiuue their present rate of development — a development largely due to the energy and ability of the senior High School Inspector — the principle of the division of labor must soon be applied in apportioning the work to be done by them. A "fixed course" of study for each of our 104 schools is unnatural, unreasonable and impracticable. As every district should have its Agricultural School, so every city should have, besides its Classical School, a Technical and Commercial one, in which young men who do not desire to take a university course could be trained in English Literature, Elementary Mathematics, Chemistry, Physics, Free Hand Mechanical and Architectural Drawing, Physiology, Short- hand, Telegraphy, Book-keeping, and the Elements of Political Economy. A. P. KNIGHT. Kingston, March, 1884. * Since the above was published the present Minister of Education has practically reduced the number of optional subjuots and consequently the number of classes which many head masters previously found necebsaiy to maintain in their schools. PREFACE TO FIRST EDITION. All the text-books on Chemistry authorized for use in the Public and High Schools of Ontario contain far too much matter for class purposes, and as a consequence many teachers have been compelled to teach the subject by the use of notes. This little book has been prepared chiefly for the purpose of lessening the labor of note- making on the part of teachers, and of note-taking od. the part of pupils. It will require to be supplemented by explanations from the teacher, for whose use most of the ordinary text-books on Chemistry seem designed. Pupils should draw diagrams of the apparatus employed, using for this purpose the blank leaves. No apology is necessary for the insertion of a large number of chemical problems. On the utility of these as a means of teaching the subject. Professor Roocoe says : — " My experience has led me to feel more and more strongly that by no other method can accuracy in a know- ledge of Chemistry be more surely secured than by atten- tion to the working of well selected problems." On this same point Professor Cooke, a leading American chemist, says in his First Principles of Chemical Philosophy: — " The value of projdlems as means of culture and test of attain- ments can hardly be over-estimated. " I have to express my indebtedness to Professor Dupuis; of Queen's College, for valuable suggestions in preparing this manual, and for kindness in reading the proof-sheets. EiNQSTON, February, 1882. •ION. )d for use in lontain far too a consequence lach the subject been prepared labor of note- note-taking on npplemented by use most of the (signed. Pupils employed, using rtion of a large utility of these •rofessor Roocoe il more and more turacy in a know- id than by atten- blems." On this oierican chemist, vilosophy: — " The id test of attain- 'rofessor Dupuis; ions in preparing the proof-sheets. ^i ' < •*^- CHEMISTRY FOR HIGH SCHOOLS. The science which treats of elementary substances^ the modes or processes by which they are combined or separated, the laws by which they act, as well as the properties of the compounds which they form, is called Ghemistri/. B The subject admits of a two-fold division ; viz., into Organic and Inorganic. Organic OhenUStry treats of the composition and properties of substances that have been formed by the agency of animal or vegetable life. More correctly defined, it is the chemistry of the Hydro- carbons and their derivatives. Inorganic Chemistry treats of the composition and properties of bodies formed without the agencj of life. It is the chemistry of water, earth and air. Atomic Theory. — All substances are supposed to be built up of very minute and indivisible particles, called atoms. It is asserted that these atoms are of different sizes, and differ from each other in weight. All substances can be divided into two classes — Simple substances or Elements, and Compound sub- stances. ^ A chemical element or simple substance is one that has not been decomposed into two or more 6 CHEMISTRY FOR HIGH SCHOOLS. dissimilar bodies. Examples: gold, sulphur, and arsenic. There are 65 of those elements ; according to some chemists 69, and from one or more of these, every 'substance in nature is built up. The following is a list of some of the most important of them, with their symbols and atomic weights : — Non-Metallio Elements. Metallic Elements. « Oxygen . . . .... = 16 Iron Pe = 56 Hydrogen .. .... H = 1 Aluminum .... Al = 27.5 ^Nitrogen . . .... N = 14 Calcium . Ca = 40 Carbon .... = 12 Magnesium .... Mg= 24 art atr CHEMISTRY FOR HIOH SCHOOLS. jnce can be drawn between metals and non-metals ^he Non-Mbtals, or Metalloids, are distinguished )y the absence of these properties. Another division Is 15 metalloids and 50 metals. Arsenic and Tellu- rium are sometimes classified as metals, sometimes as bon-metals. A compound substance is one formed by the mion of two or more of the above-named elements. Examples water, earth and wood. There are thou- sand of these compounds known to us. It is customary to distinguish between two kinds )f com[)Ounds : — 1. Chemical Compounds. 2. Mechanical Compounds or Mechanical Mix- tures. A chemical compound is one in which the elements- composing it are united in such a way as to. lorm a substance differing in properties from those of py of its constituent elements. For example, the gas Ihlorine and the metal sodium unite to form common lit — a substance differing in properties from those of ^oth chlorine and sodium. A mechanical compound is one in which the ^articles of the substances composing it lie mixed side ^y side, undergo no change, and preserve their distinc |ive j>roperties. Example — charcoal, sulphur and dtre in gunpowder. The force which, unites the particles of a mechanic..! >mpound is called culheaion. 8 CHEMIST RT FOR HIGH SCHOOLS. [r- Adhesion is sometimes defined as the phenomenon| which occurs when portions of dissimilar substances cling together. Physical States op Matter. — Every substance,] whether simple or compound, exists either as a solid a liquid, or a gas. Some substances may be made fe take any of these forms by varying their temperature. Ice, water, or steam is the same substance in thre different physical states. So, most of the elements and many compounds, may be made to take the solid liquid or gaseous form by simply altering ther tem perature. k\\ of the elements except carbon hav been melted ; all gases have been liquefied, and possi bly solidified. Cohesion is the force which makes or tends t make, bodies take the solid form. Tt is therefor opposed to heat. If, in any substance, these tw« forces counterbalance each other, the substance wil take the liquid form : if the heat be the greater force,] the substance will exist as a gas ; and if the cohesio be the greater, the body will take the solid form. Latent Heat. — The heat which disappears whe any solid is converted into a liquid, or any liquid into a gas, is called latent heat. It is imperceptible bj the thermometer, and is exp^inded in driving th( jvrirticles of a substance farther apart. On the con tiMry, when a gas or vapor assumes the liquid or solic form it gives out heat that goes by the name o Sensible Heat. Both terms are old-fashioned am objectionable. OLS. he phenomenon! lilar substanceal srery substancej ither as a solidj nay be made fc( )ir temperature, stance in three f the elements] » take the solidj ering ther tern] pt carbon hav( efied, and possij kes or tends i-c Tt is therefore ince, these tw( ? substance will jhe greater force,! I if the cohesioi I solid form. disappears wheD r any liquid intc imperceptible bj in driving th( ft. On the con he liquid or soli( by the name >ld-fa8hioned an( I \ 0HE1II8TRT FOR HIGH SCHOO?'^. 9 Distinction BETWEEN Vapors and Gases. — Vapors are substanceis in the gaseous condition, which, at ordinary temperatures, are liquids or solids. Oases are substances which exist in the gaseous condition at ordinary temperatures. Ldquefaction is the conversion of a solid into a liquid. Solidification is the conversion of a liquid into a solid. VaporiisatiOIl is the conversion of a liquid into gas- Sublimation is the conversion of a solid into a ^as without liquefaction. Condensation is the conversion of a gas into the ^uid or solid form. Distillation includes first vaporization, and then pndensation, and is carried on usually for the purpose separating a liquid from impurities contained in it. CONSTITUTION OF MATTER. I An atom is the smallest part of an element . that enter into a chemical compound. [A molecule consists of two or more atoms, and [the minutest particle of a compound or of an ele- iLt capable of independent existence. An atom (ot exist ialone, but at once unites with another Lto form a molecule. The exception to tlus is latbm of mercury and that of cadmium. i.>/ 10 CHEMISTRY FOR HIGH SCHOOLS. Ohemical affinity or chemism is the force that binds atoms together to form molecules, and molecules together to form definite chemical com- pounds. ' \ . Eflective affinity is the attraction of one element for another in preference to a third, when there is a mixture of elements uniting to form chemical com- pounds. The molecule of each element consists of two atoms; but the molecule of phosphorus as well as that of arsenic contains four atoms, while that of mercury and that of cadmium consists of one each. Molecules of compounds contain two or more atoms. The Volume of any sub^^tance is the space occu- pied by it. In chemistry, if no unit of volume be mentioned, it is frequently understood that one volume of an element or compound is the apace occupied by one moUcvle of it in the gaseous condition. Chemical Notation is the art of designating chemical elements or compounds by means of s<;mhols. A symbol is the first letter of the name of cl element. Sometimes two letters are used to dis guish one element from another beginning with • same letter. The symbols of important ^'^lements ' be found on page 6. ', ^ Each symbol stands also for a definite weig;l sd each element, called its atomic weight, { tb I00L8. 3m is the force molecules, and e chemical com- m of one element , when there is a D chemical com- I sts of two atoms; well as that of that of mercury each. ro or more atoms. I the space occu- it of volume be d that (me volume 76 occupied by one n. rt of designating Dd^tns of b^'mhoh. the name of c 9 used to dis winning with • ant v^lements ^ ' & efinite weigl a1 1 T ihii A reii A rm len )rn >iu / CHBMI8TBY FOR QIGH SCHOOLS. U The Atomic Weight of an element is the num- 3r representing how many times its atom is heavier ^han an atom of Hydrogen. The Symbol of an element stands for three distinct jhings : — (1) The name of the element. (2). One atom of the element. (3) The atomic weight of an element. A small numeral written at the lower right hand )rner of a symbol denotes that the atom and atoniic weight is doubled, tripled, etc. A chemical formula consists of two or more rmbols written side by side, and denotes that the lements for which the symbols st-and have united to )rm a chemical compound. T3ae formula of a compound substance stands for : (1) The name of the compound, (2) One molecule of the compound, (3) The molecular weight of the compound, (4 ) Two volumes of the compound in the gaseous condition. . A numeral placed before a formula multiplies every >m and atomic weight in it, as far as th^ fintt >mma, plus sign, or period. 12 CHEHISTRT FOB HI&H SCHOOLS. (( (( u (t (( (( <( The molecule, O, consists of 2 atoms. H, Na, P4 " 4 of the compound H3O consists of 3 atoms. | KCIO3 " 5 7 (( ti (( << « u u (( (( « « u (i <( (( « (( (( P205 ^16^32 (( (( 48 (( It Each of these eight molecules occupies the same] space or volume in the gaseous state. A chemical equation consists of signs andl formulse, and expresses tlie fact that definite weights! and volumes of certain substances do, of themselves,! or by means of some force applied to them, decom- pose and re-arrange their atoms so as to form other| substances. For example the chemical equation—- CaCOg + 2 HCl = CaCl, -f H3O + 00^ "^ 100 + 73 111 + 18+44 may be thus translated : mix 100 grams (or ounces)! of marble with a solution of 73 grams of hydrochloric! acid and they will yield 111 grams of calcic chloridej 18 grams of water, and 44 of carbonic anhydride. The atoms on one sH ^ of an equation must all be accounted for on the other. The chemical equatior] thoroughly understood, enables us to calculate the amount of material required to produce a givei K icupies the same CHEMISTRY FOR HIGH SCHOOLS. 13 reight of any substance; or, the quantity of the ^ubstance produced by the decomposition of a known reight of the materipl. Its importance, therefore, in rorking out chemical problems cannot be over-esti- lated. The sign -|-, plus, placed between the formulae of |wo substances means that the two substances are lixed together. The sign = , in chemistry, means " yields." I CHEMICAL COMBINATION. Chemical union may take place in certain propor- ^ons by Weighty or when the substances exist in the iseous condition in certain proportions by VoluTne ; |ut in both cases the combination is regulated by srtain laws called laws of chemical combination, fhey are usually stated as follows : — LAWS. I. Constant Proportion. — " The same substance msists invariably of the same elements," e. g.y water fways consists of O and H. II. Definite Proportion. — " The elements which • ^rm a chemical compound are always united in it, in le same proportion by weight," e. gr., O and H are [ways united, in water, in the proportion of 16 to 2. voluihe, the union is always 2 vols., of H to 1 of O. III. Reciprocal Proportion. — " If two elements ^mbine in certain proportions with a third, they com- 2 { act like licle, and 3les act as A.SURES. ages over ranch. t to 39-37 inches. inches. 1 litre ■ : m-M M \ V OA Then at 4^0, . Thee = 2-20- Thes tenths, ] prefixinj names. Thes solid is : equal v( Inth air or h The 1 on chen] has, hov sics, and for speci In CO volume one is 1 and pre£ one grai The V element! For (Bxa 11- (( u »': .1 CHEMISTRY FOR HIOH SCHOOLS. 17 MEASURE OF WEIGHTS. The unit is the weight of I cb. cm of distilled water at 4^0, called 1 gram = 15*432 grains. The commercial unit is 1000 grams = I kilogram = 2*2046 lbs. Avoirdupois. The subdivision of both the litre and the gram into tenths, hundredths, and thousandths, are named by prefixing deci-, centi-, and milli-, respectively to these names. SPECIFIC WEIGHT. The specific weight or specific gravity of a liquid or solid is its weight as compared with the weight of an equal volume of water at 4°C. In the case of gases the comparison is made with air or hydrogen. The term donsity is, according to some writers on chemistry, another name for specific weight. It has, however, an entirely different meaning in Phy- sics, and should not therefore be used as a synonym for specific weight. In comparing the weights of different gases any volume of H might be taken, but the most convenient one is 11*2 litres, which at the standard temperature and pressure of 0°C and 760 mm. of mercury, weigh one gram. The weight in grams of 11*2 litres of each of the elementary gases is denoted by its atomic weight. For iBxample : 11*2 litres of oxygen weigh 16 grams, chlorine " 35*5 " nitrogen " 14 ** and so on. K it (t (t m / i I hi CHEMISTRY FOB HIGH SOCHOLS. The sp. gravity of a compound gas is found by taking half of its molecular weight. Thus: / 1 1*2 litres of steam weigh ^= 9 gi^ms. \ 11-2 " ammonia gas weigh V = SJ " 11-2 " carbon dioxide " 4^ = 22 "and so on. THE ELEMENTS. Hydrogen : Symbol, H ; atomic weight, 1 ; molecular weight 2 / 11 '2 litres weigh 1 gram. Sources : Nearly always found in combination. Forms ^ by weight of water. Organic substances, sulphuric acid, &c., contain it. Preparation: 1. By electrolysis of water. 2. By decomposing water with a cold metal as K. Na, Ba, &c., e. g., 2 HjO + Kj = 2 KHO + Ha- 3. By decomposing steam by means of a hot metal^ e. g., Fe or Cu. 4 HjO + Fe, = FegO^ + 4 Hj. 4. Hydrogen is usually prepared from zinc and sulphuric acid, the chemical change being H28O4 + Zn = ZnSO^ + Ha. Zinc sulphate being formed and Ha being given off. Experiments: 1. Bum a jet of H. 2. Pour H upwards. 3. Send up soap bubbles. Ignite some of them. them. n I >i. ' m i '1 '.I . -H '.I : it Proper stancei bums bustioi with h takes ] to two Uses: 1. In. 2. Im 3. In Tests ; unites ously mixtu] What sulphuric To so pupils m the react compoun Thecq CHEMltiTRT FOR HIGH SCHOOLS. 19 ProportieS : Hydrogen is the lightest of all sub- stances ; is a gas without taste, color or smell ; burns with a pale flame, but does not support com- bustion or life, though not poisonous. When mixed with half its volume of O and ignited, an explosion takes place and water is formed. Soluble in water to two per cent of its volume. Uses: 1. In oxy-hydrogen blowpipe. 2. In gas-making from petroleum. 3. In filling balloons. Tests ; Bums, but does not support combustion ; unites with O to form water ; combines spontane- ously with CI to form hydric chloride when a mixture of the two gases is exposed to sunlight. EXERCISE. What weight of H can be evolved from 392 grains of sulphuric acid ? To solve this and all similar chemical problems, pupils must know the chemical equations representing the reaction that takes place when an elementary or compound substance is evolved from others. The composition of sulphuric acid is : — H, = 2 8 ^ 32 O4 = 64 Total = 98 j^'. M 20 CHEMISTRY FOR HIGH SCHOOLS. Now the question is, if 2 grains (or oz., of water will be formed in burning the gas in air ? What volume of air will be required for the combustion, assuming that oxygen forms ^ of the volume of air ? Ans. 72 grams. Ans. 224 litres. .y.A— When the volume of gAB is spoken of, It la supposed to be at the standard temperature and pressure. )of H V many 98 (Of ). rains. will be ulphurio N8. 2. litres at rs. 20. hot iron ler end. nuch are grams. taken to \,t weight 10 08. taken to 877'5. grains of Ins. 5. tbtain 20 s. 460. I. What B in air? nbustion, t litres. d to be at ^^ mH Oxygen 16 16 Sourc( comb ing I tutes Prepa 1. B; 2. B 3. I 4. I Prop cen to a as a anc aiM CHEMISTRY FOR HIGH SCHOOLS. 21 OXYGEN. Oxygen : Symbol, 0; atomic weight, 16; specific weight, 16; molecular weight, 0^, 32. 11*2 litres weigh 16 grams. Sources : Forms i of bulk of atmosphere. Found combined with organic bodies and minerals, form- ing nearly J of the weight of solid earth. Consti- tutes I the weight of water. Preparation : 1. By the electrolysis of water. 2. By decomposing some oxides by heat, e. g., HgO, MnOj, BaOj. Oxygen may be obtained by heating the red oxide of mercury (mercuric oxide) in a test tube, the equation expressing the reaction being as follows : 2 HgO = Hg2 + O2. 3. By heating potassic chlorate and MnO.^ in a glass retort : MnOa + 2 KCIO3 = 2 KCl -H 3 O2 + MnOj. 4. Hypochlorites, chlorites, and some nitrates, will yield oxygen on being heated. Properties : It is soluble to the extent of four per cent, in water, a fact of great importance in relation to aquatic plants and animals. When free it exists as an invisible gas without taste or smell. By cold and pressure it has been made to take the liquid and even the solid form ; it unites with all the ' ' I Hr.' rm ' Ji 22 CHEMISTRY FOR HIGH SCHOOLS. other elements, except flourine, to form oxides; powerfully supports cpmbustion ; and is that ele- ment in air which sustains animal life, hence called vital air. In respiration we simply take oxygen into the system, and this causes slow combustion of the tissues, and consequently gives rise to animal heat. Experiments : Sulphur, potassium, phosphorus, charcoal, a piece of wood, steel- wire, and zinc foil, may be burned in jars of the gas. Ordinary com- hustion or hwming is simply chemical action, attended by great heat and light, chemical com- pounds being formed. Tests : Oxygen is the great supporter of ordinary combustion. A glowing splinter of wood bursts into flame when plunged into it. Nitric oxide forms reddish fumes with oxygen. Potassic pyro- gallate absorbs oxygen, and is changed to a black color by it. OZONE. Ozone : Symbol, O3 / molecular weight, 48. This substance is merely a modified form of oxygen, being one in which there are supposed to be three atoms in the molecule instead of two. Preparation : 1. By the silent discharge of electricity through oxygen. Thus treated, O decreases in bulk by A. , WXWirtMllWtMr fiitMu^MA ~. 2. By ; bo of 3. It ifi in( Propert sive od mercur underg' great d ing ag< said to of the ''Test : C and sti 1. How to obtain 2. I wj potassic < water, ho 3. AgJ potaBsic ( fiUit? 4. 251] What vo steam is CHEMISTRY FOR HIGH SCHOOLS. 25 2. By placing a stick of clean phosphorus in a bottle of air with a little water on the bottom of it. 3. It is produced in small quantities by almost any molecular disturbance of oxygen. Properties : Ozonized oxygen has a strong, oppres- sive odor ; corrodes india-rubber ; oxidizes silver, mercury, and many other metals, and, in doing so, undergoes no diminution in volume; possesses great disinfecting powers, and is a powerful bleach- ing agent. If breathed in small quantities it is said to be beneficial in the treatment of affections of the throat and lungs. 'Test : Ozone turns a mixture of iodide of potassium and starch a blue color, but this test is not reliable. EXERCISE. 1. How many pounds cf potassic chlorate must be taken to obtain 144 lbs. of oxygen ? Ans. 367*8. 2. I want 220 grams of oxygen. If I obtain it from potassic chlorate, how much of it must I use? If from water, how much ? If from mercuric oxide, how much ? Ans. 561-9. Ans. 247*6. Ans. 2970. 3. A gas bag is capable of containing 66 litres, how much potassic chlorate must be taken to procure enough oxygen to fill it ? Ans. 204^ grams. 4. 26 litres of oxygen are exploded with 36 of hydrogen. What volume of gas (if any) remains? What volume of steam is produced ? And what is its weight ? Ans. 7 litres of 0. Ans. 36. Ans. 44*8. . ' 'Tn^HB •^ '^ ] .ii^^^B ^T^W r H '4 ^ 1 'M - ,;' •■ i'w pfl 1 li 1 ^j-M| 'yW K •' ^ li ^ '^' ' i ~Ki'''n I Itm I • ' l*'ilH % -■it 1 mm f 1^' 1 j lll^ Is / 1 ifl ^ 1 ism 1 fl J ' w' rfl^^^^H 24 CHEMISTRY FOR HIGH SCHOOLS. 5. How much oxygen can be obtained from 435 grams of manganese dioxide by heating it to a red heat ? Ans. 53'3. 6. What volume will 80 grams of oxygen occupy at the standard temperature and pressure ? Ans. 56 litres. NOMENCLATURE, Chemical Nomenclature is the system of naming chemical compounds. I. In naming binary compounds, or compounds of two elements, we attach both prefixes and affixes to the names of the elements. 1. -ic is generally attached to the name ef the first * element. 2. -IDE is attached to the name of the second element. tM0^ For example, %.(jI is named potass^ chlor-iDE. -URET is an old ending, sometimes used instead of -IDE. 3. Compounds op Oxygen with other elements, when one, two, three, four, or five atoms of oxygen •enter into the compound, are, with some exceptions, called respectively mon-oxide, di-oxide, tri-oxide, tetr- oxide, pent-oxide, of the first element. 4. Another mode of designating the compounds of oxygen is by using the endings -ous and -ic, both being attached to the first element ; the former, when a smaller quantity of oxygen enters into the compound ; the latter, when a larger quantity. The affixes -ous and -ic are used in a similar way to denote binary * .'•■i CHEHISTRT FOB HIOH 8CH00U. 25 compounds of chlorine and sulphur with other elements. 5. Sesqui-oxidu and sub-oxide are old terms. t EXERCISE. Name the following binary compounds : NaCl, GuS, NgO, N,Oa, NaO„ NjO*, N,0„ HCl, H,8, CO, CO,, CaCl.,, CSa, PaOg, CuO, HgO, KjO, FeO, Fe^O,, AsaO,, AsaOj. II. Hydrates or Hydroxides are compounds formed by the union of an element, or radicle, with the monad radicle OH (Hydroxyl), e. g. : KHO is called potassic hydrate. Ca (0H)2 is called calcic hydrate. Hydrates are divided int'^ two great classes : AciD& and Babes. Generally speaking, hydrates of the metals are bases, and hydrat/es of non-metals are acids.. We can also divide oxides into acid oxides .ind basic oxides, according as the corresponding hydrate is an acid or a base. Acids possess the following properties : 1. They have usually a sour taste if soluble. 2. They change blue litmus red. 3. They act upon a metal giving up hydrogen,. which they all contain, for the metal. 4. They act upon basic oxides forming water, ^nd. neutral compounds, called salts. 1 I 26 CBEMI8TRT FOB HIGH SCHOOLS. fe' In naming acids the terminations -ous and -ic, and the prefixes hypo- and per-, are used, e. g. : HCIO is called hypochloroiis acid. HClOa is called chlorous acid. HCIO3 is called chloric acid. HCIO4 is called perchloric acid. For the least amount of O present in the above compounds, hypo ous is used ; -ous, for more oxygen ; -ic, for still more of it ; and per ic, for the greatest amount. Bases : 1. Have an alkaline taste if soluble. 2. Restore to blue the color reddened by an acid. 3. Have generally properties the opposite to those of an acid. Salts, when normal, possess properties that are neither acid nor basic. They are formed by acids acting upon : 1. A basic hydrate. 2. A basic or neutral oxide. 3. A metal. 4. Theoretically, by replacing the H of an acid with a metal. For example, the acid HNOs, with the metal K, forms the salt KNO3. Salts are named chiefly from the acids which form them. If the acid end in -ic, the salt ends in -ate. If the acid end in -ous, the salt ends in -ite. nd -ic, and 1. the above for more IC, for an acid, ite to those )s that are d by acids a acid with [NOg, with >8. ^hich form TB. ITE. J ' Pip i' 11 i i 11 'it 1 ■ i|l i 1 J '■■ i =1 mt The ] salt, e. i Acid. HCIO HaSO, HNO» HOlO* The pi the theo water af water oi to form two ato] of wate two ato: of the the oxi< 1. A of the slum, i 2. Nl CHEMISTRY FOB HIGH SCHOOLS. 27 The prefix of the acid is retained in naming the salt, 6. g. : Acid. Nahb. Salt. Name. HOlO hypochlor-ous acid. KCIO potassic HTPO-chlor-iTB. HaSO, Sulphur-ous acid. NajSO, sodic sulph-iTB. HNO, nitr-io acid. AgNO, argentic nitr-ATB. HOIO^ perchloric acid. KCIO^ potassic PER-chlor'ATU. EXERCISE. The principle of atomicity may be employed in forming the theoretical oxides and hydrates of the metals by using water as a type, and substituting in a single molecule of water one atom of a monad metal for one atom of hydrogen to form a hydrate, and two atoms of a monad metal for the two atoms of hydrogen to form an oxide. In two molecules of water, we must substitute one atom of a dyad metal for two atoms of hydrogen to form the hydrate, and two atoms of the dyad metal for the four atoms of hydrogen to form the oxide. For example : r«pe. Hyixaii. Omdt, H,0 KHO K3O 2H,0 Oa(HO)a CaO 1. Apply this principle and form the hydrates and oxides of the following metals : Sodium, silver, mercury, magne- sium, iron, tin, platinum. 2. Name the compounds thus formed. i„li Ci'ii si \ t>f i-H 28 CHEMISTRY FOR HIGH SCHOOLS. COMPOUNDS OF OXYGEN AND HYDROGEN. These are iwo in number, but the only important one is water. WATER. Formulay H^O ; molecular weight, 18 / sp. gr. at 4°C, I ; sp. gr. in gaseous state, 9 ; freezes at 0°G ; and vaporizes at 100° C ; point of maximum density, 4°(7. Properties : It is a tasteless, inodorous liquid, of a bluish green color, and can be obtained pure by distillation only j rain water is the product of natural distillation, but even this contains traces of carbonic acid, ammonia, nitric acid, and gases of the air. Impurities : Spring water contains sodic chloride (salt), calcic carbonate, calcic sulphate, small quantities of magnesic carbonate and sulphate, silica and a variety of other substances. The solid soluble impurities of water may be removed by distillation ; insoluble impurities by fil- tration. Liquid impurities can, as a general rule, only be removed with extreme difficulty, and never by distil- lation. Gaseous impurities tnay be removed in large part by boiling or by filtration through charcoal or spongy iron. The impurities in city well water are ammonia, the nitrites and nitrates of calcium and sodium, and iVi M EN. M)rtant i %t 4°(7, t 0°C; iximum q[uid, of 3ure by duct of races of ^ases of chloride f small iilphate, may be i by fil- only be y dlstil- •ge part spongy lia, the m, and •!f7 (-(.= 1'^ • ' Mi I ■ , I > m'i^ '^if. :i! '■I'll '^ (■», ii-ii ^, C'.P' worst of ning wat its motio oxygen it mal and innoxioui The t the pres( and may lime. Perm and mag sulphates washing Wat( requires stances a Watei gen by i the prod of oxyge of hydro sis of vi hydroge water, gaseous the one two of times af 'l^ I' CHEMISTRY FOB HIGH SCHOOLS. 29 worst of all, the drainage from animal refuse. Run- ning water is fitter for d jinking than stagnant, because its motion exposes a fresh surface to the air, so that oxygen is continually absorbed and oxidizes the ani- mal and vegetable matter in the water, forming innoxious compounds. The temporary hardness of water is due to the presence of calcic or magnesic carbonates in it, and may be removed by boiling or by treating with lime. Permanent hardness is due to salts of calcium and magnesium, other than the carbonates, such aj^ sulphates and nitrates, and may be removed by adding washing soda (sodic carbonate). Water of crystallization is that which a salt requires in order to crystallize. AnhydroUS sub- stances are those free from water in combination. Water may be decomposed into oxygen and hydro- gen by means of electricity. When this is done, and the products weighed, we observe that the one volume of oxygen weighs 8 times as heavy as the 2 volumes, of hydrogen produced in the process. The synthe- sis of water by the Evdiometer shows that 2 vols, of hydrogep unite with 1 of oxygen to form two of water, Ldnoe the specific weight of water in the gaseous condition is 9. In the analysis of water, the one vol. of oxygen weighs 8 times as heavy as the two of hydrogen, hence vol. for vol. oxygen is 16 times as heavy as hydrogen. 3 -■) ttl f' .;fl i' ' l\ i: li n 1..11.. 30 CHEMISTRY FOR HIGH SCHOOLS. Law op Avooadro.— Equal vols, of gases at equal temperature and pressure contain the same number of molecules. N From this law it follows, that one molecule of weighs 16 times as heavy as one of H. Hence also the atom of O is 16 times heavier than the atom of H. The presence of any considerable amount of ammo- nia in water renders the advisability of using such water for culinary purposes very doubtful. Ammonia can be detected in water by applying the following test : — Nbssler's Test for Ammonia. — " To a solution of potassic iodide add solution of mercuric chloride until the precipitate formed is nearly all re-dissolved, then add an equal volume solution of caustic potash, and allow the whole to stand until clear. A few drops of this solution will give a yellowish-brown precipitate, with even the slightest trace of ammonia." NITROGEN. Nitrogen: Symbol, N ; atomic weighty li grams ; spe- cific weightf 14; molecular weight, 28. 11 '2 litres Weigh 14. Sources : Constitutes four-fifths of air, thus diluting the ; found in plants being a constituent of some of the strongest poisons such as prussic acid and strychnine; component also of bread, milk and flesh of animals. ses at mtain le of ice also >m of H. ammo- Qg such mmonia oUowing lution of de until ed, then Etsh, and drops of )cipitate, li- . \ 1 ■ i< ,-0 •s, >v ^ t^ I Cif^irr / -4- M-< ■If fe:. 8. 11-2 diluting ; of some acid and lilk and 'JjSMi'i ill I i! :!i y -Jr Prepare 1. Iti 2. By 3. By ni Experi] 1. She 2. She Propen smell ; life; ] not su to the DOt ui excep Tests: hi dis prope 1. Wh from 448 2. AsG akr, wh». ingai g sir throi 3. Ho CHEMISTRY FOR HIGH SCHOOLS. 31 Preparatiou : 1. It is obtained by burning phosphorus, or some other combustible, in a bell-jar over water, the oxygen being burned out and nitrogen remaining. 2. By passing purified air over red hot copper. \ 3. By heating a strong solution of ammonium nitrite ; NH^NO, = N^+^HjO. Experiments : "~ 1. Show that it will not support ordinary combus- tion. 2. Show that it will not bum. Properties : Nitrogen has neither color, taste, nor smell ; is a little lighter than air ; will not support life ; has been liquefied by cold and pressure ; does not support ordinary combustion ; soluble in water to the extent of two per cent, of its volume. Does not unite readily and directly with other elements, except boron and titanium, to form nitrides. Tests : It does not support common combustion, and in distinguished in a general way by its negative properties. EXERCISE. 1. What weight and volume of nitrogen can be obtained from 448 grams of nitrite of ammonia ? Ans. 196 grams ; 166'8 Utres. 2. Assuming that iixitrogen constitutes J of the volume of akr, whp.t weight of cnpdc oxide would be formed in obtain- ing 8-1 grams of uitroj^'^'i by passing a sufficient quantity of sir through a tube oontaining copper filings ? Axs. 11 9 '25 grams. S. How many litres will 210 grams of nitrogen occupy ? Airs. 168 litres. Ml ." If l^ff! ! [ ii'':i'. 32 CHEMISTRY FOR HIGH SCHOOLS. COMPOUNDS OF NITROGEN. Ammonia : (Spirits of Ha/rtshom) Formula^ NH^ ; atomic weighty 17; specific weighty 8 '5. 11*2 litres weigh 8*5 grams. Sources : it occurs in the urine and in some other products of animals, also in air as the result of the decay or combustion of animal matter. Preparation : 1. Formerly obtained by distilling portions of bone, ivory, horn, parchment, feathers, silk. 2. Now from the waste liquors produced by the dest'^ictive distillation of coal. 3. May be obtained in the laboratory by heating sal-ammoniac (ammonic chloride) and quick lime : 4^ 2 NH^^Cl + CaO = 2 NH3 + CaClg + HaO. 4. Most conveniently obtained by simply heating some liquor ammonise. Experiments ! 1. Pass the gas into a solution of turmeric, and into one of reddened litmus. 2. Show its rapid solubility in HjO, using a narrow- necked bottle. 3. Show the white cloud produced with a volatile acid, e. g.y HCl. Properties : is a colorless gas with an alkaline taste and pungent smell ; soluble to upwai-ds of 700 h.. NH 11-2 le other t of the of bone, Ik. by the heating id quick heating '■\\'i and into narrow- volatile i I! ine taste lBof700 Tests : Nesslei Ammoi This C( water, ar 1. Galci occupy. 2. 112 meter, w Asa. 3. Whi tained fro 4. If eudiomet oonstitue the volui 5. Wh 107 gram of the of ammo Ans CHEMISTRY FOR HIGH SCHOOLS. 33 times its bulk in water at 1 &°0, which is then called liquor ammoniaB ; is powerfully alkaline ; becomes liquid at - 40°, may even fi-eezeat -75°. Tests : Its smell ; its solubility in water. See Nessler's test, under the notes on water. Ammonitim Hydrate, NH^HO, or NH^, H^O. " Liquor Ammonice." This compound is formed by dissolving NH3 in water, and is a most powerful base or alkali f^ !'' :^tm EXERCISE. 1. Calculate what volume 51 grains of ammonia gas will occupy. Ans. 67 '2 litres. 2. 112 litres of ammonia gas are decomposed in a eudio- meter, what volume will its constituent gases occupy? Ans. 28 litres of nitrogen ; and 84 litres of hydrogen. 3. What weight and volume of ammonia gas can be ob- tained from 214 grams of ammonic chloride ? Ans. 68 grams ; 89 '6 litres. 4. If 85 grams of ammonia gas be decomposed in a eudiometer, and 22*4 litvu: '■1 oxygen gas be added to the constituent gases, and the mixture exploded, what will be the volume of the resulting gases at 0°C. Ans. 28 litres of nitrogen ; and 39 '2 of hydoogen. 5. What weight of quick-lime is required to decompose 107 grams of ammonic chloride, and what will be the weight of the calcic chloride and water produced? What volume of aomionia gas will be evolved ? Ans. 66 grams of lime ; 111 of calcic chloride ; 18 of water : and 44* litres of ammonia. If m. H CHEMISTRY FOR HIGH SCHOOLS. COMPOUNDS OP OXYfJEN AND HYDROGEN. Oxygen forms with nitrogen five known compounds: Namss. POB- Older Names. 1 CORRBSPOMOINO ACIDS. Nitrogen Monoxide. Dioxide. Trioxide. Tetroxide. Pentroxide. N^O. NO. N,0,. NO,. N^O,. Nitrous Oxide. NUric Oxide. Nitrous Anhydride Nitrogen Peroxide. Nitric Anhydride. HNO Hyponitrom Add (not eliminated). HNO, Nitrous Acid (not eliminated). HNO^ Nitric Acid (well knovni). The first three oxides are important. Nitric acid is also. Nitrous Oxide (" Laughing gobs ") : fwmula^ N^O ; molecular weight, 44; 8pec\ftc weight, 22. 11*2 litres weigh 22 grams. # Preparation : Heat ammonium nitrate in a retort. Reaction : NH^NOa = 2 HjO + N^O. Experiments : 1. Plunge a lighted taper into a jar of the gas. 2. Bum P in it. 3. Explode a mixture of N,0 and hydrogen. EN. K>unds: NO Acids. ponitrom lated). rouaAdd inated). trk Acid )wn). iiic acid 2. 11-2 a retort. m ii ' ; Hi! ;i i I) Ml i 1 ^>:f.S ■ffi ■ "i ' ',Vi 1 gas. n. J t J 11 ?■ Propert and sw inhaled bility. Tests: Bolubili oxygen Nitric C Prepare with n OusJ Ezperi 1. Sh< 2. Mi Propel not so Tests ; when Mtrotu spec Prepa 1. ^ CHEMISTRY FOR HtOH SCHOOLS. Properties : A colorless gas with a pleasant 8m«ll and sweet taste. Supports combustion, and when inhaled produces transient intoxication and insensi- bility. Used as an anaesthetic. Tests : Distinguished from oxygen by its gii'eatei solubUity. Phosphorus burnt in N3O takes out oxygen, without lessening the volume. Nitric Oxide, NO ; molecular weight, 30 ; specijic weight, 16. 11*2 litres weigh 15 grams. Preparation : Act upon copper, mercury or zinc with nitric acid. Thus : Cus + 8 HNO, = 3 Cu(N03)a + 4 H,0 + 2 NO^ Experiments : 1. Show that it will not support the combustion of a candle, but will that of phosphorus. 2. Mix the gas with air or oxygen. Properties : Supports combustion of a hot flame ; not soluble to any fp:^a,t extent in water; is colorless. Tests : Forms a red gas when it escapes into air, or when oxygen is added to it — product N3O, and NOj mixed. Nitrous Anhydride, NjO^ ; molectda^ weight, 76 ; specific weight, 38. 11 '2 litres weigh 38 grams. Preparation : 1. Mix 4 volumes of NO with 1 volume 0. Thus: 4 NO + O, = 2 N.O,. \ 36 CHEMISTRY FOR HIGH SCHOOLS. Properties : A Teddish-omnge colored gas ; easily condensed into a liquid by a temperature of - 18°C. When passed into ice water it dissoves to a blue liquid and to NltroUS Acid, the type of a series of salts called Nitrites. Test : Its color when pure and when dissolved in ice water. EXERCISE. 1. A dentist wishes to obtain 56 litres of nitrous oxide, how much ammonium nitrate must be used to evolve it ? Ans. 200 grams. 2. Calculate what volume of nitrous oxide can be obtained from 320 grams of ammonium nitrate. Ans. 89 '6 litres. 3. In question (2) calculate the volume in cubic inches. Ans. 6467*76 cubic inches. 4. How much copper and nitric acid must be used in order to obtain 180 grams of nitric oxide ? Ans. 571*6 and 1612 grams respectively. 6. If a piece of phosphorus be burned in 22 grams of nitrous oxide, what gas and what volume of it will remain ? Ans. 11*2 litres of N. Nitric Acid : Formula, HNO^ ; molecular weighty 63 ; speci^c weight of liquid^ 1*62; boiling point, 84*5° Freezing, -40°. Sources : Formed in the air by electricity. Exists also in nature in the form of nitrates of potash, soda and lime, which are themselves the product of the decomposition and oxidation of mti'ogenous organic compounds with alkalies. Prepaj 1. It 2E The 2. So Exper 1. A( 2. Tl 3. A( KOTB.— ( Prope comp solve formi act s UBdS: in cl Test: imps of f« CHEMISTRY FOR HIGH SCHOOLS. 37 Preparation : 1. It is prepared for use in the arts from the mine- rals sodic or potassic nitrate by treating them with sulphuric acid, and distilling ; the reaction being as follows : 2 KNO3 + H^SO^ =. HKSO, + HNO3 + KNOg. The acid distils over. By applying more het\t the HKSO4 + KNO3 = K2SO4 + HNO3. 2. Sodic nitrate may be used instead of potassic nitrate in the above equations. Experiments: 1. Add HNO3 to phosphorus. 2. Thrbw burning charcoal upon fuming HNO3. 3. Add HNO3 to carbolic acid, KoTB. — (Theae experimtints must be performed with care). Properties : When pure it is colorless ; is easily de- composed ; is a strong oxidizing agent ; and dis- solves or attacks nearly all the common metals, forming salts with them. Nearly all strong acids act similarly. Uses : Is used in dyeing, metallurgy, medicine, and in chemical analysis. Test : It bleaches indigo. With sulphuric acid it imparts a brown, purple or black color to a solution of ferrous sulphate (FeSO^). lii (■ I i'i 111 ■I ii I f" 38 CHE^ilSTRV iOE *KiaH SCHOOLS. EXEi.u;ibJi:. The principle of atomicity may be e>aployed in fonuing theoretical salts, by replacing one atom of the hydrogen of an acid with one atom of a monad metal ; two atoms of the hydrogen of an acid with one atom of a dyad metal, and so on. For example : Add, Salt. NaiM of Salt. HNO, AgNOa Silver Nitrate. HaSO^ ZnSO^ Zinc Sulphate. 1. In the same way symbolize the salts which nitric acid may form with the following metals : Potassium, calcium, copper, lead. 2. Name these salts. i 3. Symbolize and name the salts which chloric (HGIO,) and sulphuric (H3SO4) acids may theoretically form with sodium, potassium, magnesium, copper, lead, calcium and iron. EXERCISE. 1. What weight of nitric acid can be obtained by the de- composition of 505^ grams of nitre by sulphuric acid, and at a moderate temperature ? Ana. 157*5. 2. If 189 grams of nitric acid and 408*3 grams of hydro- potassic sulphate are produced in obtaining nitric acid from nitre and sulphuric acid, what quantities of these ingredients must have been used ? Ans. 303 '3 grams of nitre ; and 294 of acid. 3. What weight of "laughing gas" can be got from 240 grams of ammonic nitrate ? What weight of water is pro- duced in the decomposition ? Ans. 132 grams ; and 108 grams water. 4. What volume will 132 grams of nitrous oxide occupy ? Ans. 67*2 litres. 5. What volume will 120 grams of nitric oxide occupy ? Ans. 89*6 litres. 6. Ho^ of nitric a The I pressing inch of t it are mi the folio 1. Ther( bet 2. Onr tions, 3. The ox th( 4. Niti re of The foUowt Oxygen Nitroge Aqneoi Carbon Traces snip OHEMISTRT FOR HIGH SCHOOLS. 89* 6. How much nitric oxide can be obtained from 604 gramr of nitric acid by adding to it a sufficient quantity of copper ?' Aks. 60. THE ATMOSPHERE. 11*2 litres weigh 1444 grams. The atmosphere is an ocean of mixed ga^es pressing with a weight of 14*7 lbs. upon every square inch of the earth's surface. That the gases composing^ it are mixed — ^not combined chemically — is proved by^ the following considerations : 1. There is no simple relation in volume..jor weight between the gases composing it. 2. On mixing its constituent gases in proper propor- tions, no visible or thermotic changes occur. 3. The air dissolved in water does not contain' oxygen and nitrogen in the same proportions as they are found in the atmosphere. 4. Nitric oxide passed into free oxygen or air forms- red fumes — never when passed into compounds of oxygen and nitrogen. The average composition of air is about m follows : Oxygen, including Ozone 206'1 cub. centimetres.. Nitrogen 779*6 " Aqueous vapor 14 " Carbon dioxide '4 ** Traces of ammonia, nitric acid and } sulphuretted hydrogen. ) Total.... 1000- ** u ' If- 1 40 CHEMISTRY FOR HIGH SCHOOLS. \' In large towns, sulphurous anhydride and sul- phuretted hydrogen are present in air in small quan- tities. Minute particles of solid organic matter are .:also found floating through it, such as spores and fungi, and the supposed germs of disease. The source of carbon dioxide in the air is respira- tion, combustion and decay, &c. It supplies carbon to plants. The source of ammonia is the decay of organic ^matter. It furnishes nitrogen to the soil, and thence to plants and animals. Carbon : Symbol^ C ; atomic weighty 12 ; specific gravity f as diamond, about 3-4. .Sources : Occurs in three allotropic forms : 1. Crystalline, as diamond. 2. Graphitic, as graphite, plumbago or black- ilead. (This is a crystalline form also). 3. Amorphous, as charcoal and coke. It is the characteristic element in all organic com- 'poui^ds. Diamond is pure carbon crystallized, and may be burned in the arc of the voltaic battery — product, carbonic anhydride. Plumbag^O is found :as a mineral ; used for making drawing pencils, for stove polish, and for making crucibles when mixed with clay. There are many varieties of the amorphous form of ^carbon. The following are the principal ones : t'li r i ' m It;: (i:t (»)P portion, smaller, tion of I the sub ages ag( the coml and of r (b) A of carbo closed ii gas and gen, nit the resi< maniifa< may be gaseous vmeg( ducts j charcoa anothei (d) heating and is agent. Uses is a its c CHEMISTRY FOR HIOH SCHOOLS. 41' (a) Pit Goal, composed of carbon in large pro- portion, oxygen in smaller quantity, hydrogen in smaller, nitrogen in still less, and, a variable propor- tion of saline and earthy matter ; has been formed by the submersion of huge forests under the sea, long: ages ago, the wood being slowly changed into coal by the combined action of the pressure? of water upon it, and of moderate heat from the interior of the earth. (b) Anthracite coal contains about 90 per cent, of carbon. When bituminoUS coal is heated in. closed iron cylinders free from air, a large quantity of gas and tar is formed, containing the oxygen, hydro- gen, nitrogen, and some of the carbon of the coal ;: the residue is called COke. This is how coal gas is manufactured. This process of destructive distillation may be applied to wood also, when an inflammable gaseous product will be given off; WOOd-tar, vinegar and WOOd-naptha, are the liquid i)ro- ducts; the black porous mass left behind is called charcoal. (c) Lamp-blacky the basis of printer's ink, is- another form of carbon. (d) Animal charcoal or ivory black is made by heating the bones and flesh of animals in iron retorts, and is used in refining sugar, and as a decolorizing: agent. Uses : Its chief use is, of course, for fuel. Charcoal, is a good disinfectant and antiseptic, on aecount of its absorbent and purifying power. Its purifying; ',*■ I. i- '< pi i 42 CHBMISTBT FOR HIGH SCHOOLS. power is due to the action of the oxygen condensed from the surrounding air within the pores of the charcoal. Charcoal is used for making water filters, and is also the great reducing agent of the metal- lurgist. COMPOUNDS OF CARBON AND OXYGEN. {yarbon Monoxide (Carbonic Oxide) : Formula^ GO ; molecular weight, 28; specific weight, 14-. 11 '2 litres weigh 14 grams, Sources : This gas is formed by ordinary combus- tion in our coal stoves, and causes the " blue blazes" that are seen flickering over the top of coal fires. Preparation : 1. By passing carbon dioxide over red hot charcoal. CO2 + C = 2 CO. 2. By heating oxalic acid and sulphuric acid in a retort. The latter takes from oxalic acid the elements of water, and the residue breaks up, forming a mixture of the two gases — carbon dioxide and carbonic oxide. Thus : C2H2O4 + H2SO = H2O, H2SO, + CO2 + CO. The carbon dioxide is absorbed on passing the mixed gases through a solution of caustic potash. Properties : It is a colorless, tasteless gas, and violently poisv>nous when breatht^d. It burns with a pale blue flame, taking up oxygen and forming carbon dioxide. , 'Ml I 4 ■■I [ ■■ !|l Bxperi 1. Bu 2. Pa Tests : of tht milky water Gai'boni gat 44 gn Sourct dantl conti putr prdii lates som( crat< com Prepj 1. ] 2. : CHEMISTRY FOR HIOH SCHOOLS. a Experiments : 1. Bum a jet of the gas. 2. Pass the gas through benzine and then bum it. Tests : The color of its flame. The product (OOa) of the combustion of this gas turns lime water a milky color. The gas itself does not affect lime water. Carbonic Anhydyide {Garbon dioxide, ca/rbonic cusid gas, choke damp) : Formula, CO^ ; atomic weight, 44 ; specific weight, 22. 112 litres weigh 22 grams. Sources : In respiration, this gas is given off abun- dantly ; the air which has been breathed once contains from 3 to 4 per cent, of it. Fermentation, putrefaction, decay, and germination, as well as all ordinary combustion, give rise to it. It accumu- lates in old pits, wells, and mines, and issues sometimes from fissures in the earth and from the craters of volcanoes. It exists very abundantly in combination with lime and magnesia. Preparation : 1. Is usually made by treating chalk or marble with hydrochloric acid, the decomposition being: CaOO., + 2HC1 =r OaCla + HaO + OOa. 2. By pouring a strong acid upon any carbonate, e.g., K3CO3, NaaCOg, «fcc. V i ; !;:4 m:4 |i Ji'r If' 44 CHEMISTRY FOR HIGH SCHOOLS. Experiments : 1. Place a lighted taper in a jar of the gas. 2. Pour the gas from one jar to another. 3. Pass the gas through lime water. 4. Pass air from the lungs through lime water. 6. Absorb some of the gas with caustic potash. Properties : CarbonvMM*hydride is a heavy transpa- rent gas without color. It may be condensed to a liquid by applying cold and a pressure of 40 atmos- pheres, or it may be generated as a liquid in strong iron tubes ; it may even be frozen to a snow-white solid, which, when mixed with ether, produces a freezing mixture of - 75°. When heated it accumu- lates in the upper part of the room, and therefore, in ventilating a room, openings should be made for its escape near the ceiling, whilst fresh air should be admitted near the floor. Its vitiating effects upon the atmosphere are only prevented by the action of plants upon it, which, in the presence of sunlight, decompose it, retain the carbon and give out the oxygen. It does not support combustion. Test : Ti test for this gas is lime water, which it renders turbid, owing to the formation of chalk. It does not burn, cannot be breathed pure, but mixed (from 3 to 4 per cent.) with air, it acts as a narcotic poison, and produces death. ;er. "" ksh. ;ranspa- 3d to a ) atmos- L strong i^-white iuces a iccumu- fore, in 3 for its ould be ts upon ction of inlight, Dut the hich it %lk. It ) mixed larcotic ■« 1*' iff * ,?ii^^ -i'li i : .iil 1 1 II i if i' \\ u 1. Hov grams of 2. H 1 charcoal, What we: 3. 20 1 What gat 4. Hov carbon di 5. Wh carbon? 6. Inc combnsti 7. Wi 8. Wl 9. Wl 250 grail 10. W must be 11. \S 12. II acid, fin CHEMISTRY FOB HIGH SCHOOLS. 45 EXERCISE. 1. How much potassium will be required to decompose 110^ grams of carbon dioxide ? An3. 391 grams. 2. If 10 litres of carbon dioxide be passed over red hot charcoal, what gas, and how many litres of it, will be formed ? What weight of it ? Ans. 20 litres ; 25 grams of GO. 3. 20 litres of carbonic oxide are burned in oxygen gas. What gas is produced, and what volume and weight of it ? Aks. 20 litres ; 39*2 grams of GO,. 4. How much carbon can be obtained from 264 grams of carbon dioxide ? Ans. 72 grams. 5. What volume of oxygen is required to bum 66 grams of carbon ? Ans. 123*2 litres. 6. In question (5) what volume of air would be needed for combustion ? Ans. 616 litres. 7. What volume do 110 grams of carbon dioxide occupy ? Ans. 56 litres. 8. What volume do 140 grams of carbonic oxide occupy ? Ans. 112 litres. 9. What weight of carbon dioxide can be obtained from 250 grains of pure limestone by treating with hydric chloride ? Ans. no grains. 10. What weight of carbonate of lime and hydric chloride must be decomposed, to produce 352 grams of carbon dioxide ? Ans. 800 ; 584 grams. 11. What volume will 98 grams of carbonic oxide occupy; Ans. 78*4 litres. 12. If 270 grams of oxalic acid be decomposed by sulphuric acid, find the volume and weight of the gases produced. Ans. 132 grams ; 67*2 litres of COg. Ans. 84 grams ; 67.2 litres of G. >■ ■■ m i>j' :^i '§^'k i:. fi 4fi CHEMISTRY FOR HIGH SCHOOLS. 13. What volume of carbon dioxide will be produced by the combustion of 24 grams of carbon in oxygen gas ? Ans. 44*8 litres. 14. Calculate the weight and volume of carbon dioxide produced by the combustion of 42 grams of carbonic oxide ? Ans. 66 grams ; 33*6 litres. COMPOUNDS OF CARBON AND HYDROGEN : HYDROCARBONS. / r These are very numerous, and their /ull considera- tion belongs to organic chemistry. T^e simpler ones exist as gases, the more complex, as liquids, and the most complex in composition, as solids. All are im- flamraable. Only three will be noticed here : Marsh gas, ^cetylene, and Ethylene. / Ma/rsh Gas {Light carhuretted hydrogen, " Fire-damp"), CH^ ; molecular weight, 1 6 ; specific weight, 8. '11-2 litres W0igh 8 grams. Sotirces : This substance is generated in mai'shes by the decomposition of vegetable matter containing carbon and hydrogen. Formed in coal mines also, and on being mixed with air and ignited, causes fearful explosions — product 00^ and H^O. To pre- vent these. Sir H. Davy invented bis Safety Lamp. Preparation : strongly heat one part sodic acetate, and four parts sodic hydrate, and quick lime. Reaction : NaC^HgO, + NaHO = Na^CO, + CH4. The quick lime probably acts by Catalysis. duced by I litres. 1 dioxide lie oxide ? > litres. Dnsidera- jler ones and the are im- : Marsh 'ht, 8. ai-shes by jntaining ines also, d, causes To pre- Safety c acetate, Lck lime. I,. lis. ,M I i I If m IMAGE EVALUATION TEST TARGET (MT-3) 1.0 u 1^128 |25 <^ Uii ■2.2 !!? lift "^ IM |l.25 1 ,.4 ^ < 6" ► Photographic Sciences Corporation 23 WIST MAIN STRUT WIUTM.N.Y. USM (7U)t73-4S03 CHEMISTRY FOR HIGH SCHOOLS. 47 Properties : Colorless, invisible, odorless gas ; scarcely soluble in Hj,0; does not support com- bustion or respiration ; burns with a pale, almost non-luminous flame. Experiments : 1. Bum a jar full of the gas. 2. Explode a mixture of 1 vol. of CH^ and 2 vols, of O. Its combustion : CH^ + 2 O^ = CO2 + 2 H2O. Remc^mbering that every molecule occupies two volumes, this equation may be translated thus : Two vols, of CH4 burnt with 4 vols, of yields two vols. CO2, and four vols, of -^apor of H2O. Assuming that constitutes | of the air, it will re- quire 10 vols, of air to furnish oxygen enough to bum one volume of CH4. Tests : Pale flame, and deposition of black soot upon porcelain held in its flame. This latter dis- tinguishes it from H. When passed through a tube containing intensely hot pumice stone, one vol. of it breaks up into two vols, of H, and C is^ deposited on the stone. EXERCISE. 1. Oaloulate what quantities of sodic acetate and sodia.. hydrate must be decomposed to yield 134 '4 litres of marsh gas. Ans. 492 and 240 grams respectively. 2. If 10 litres of marsh gas be passed through a tube con- taining intensely heated pumice stone, what gas and what, volume of it will be eliminated ? Ans. 20 litres of H. ill III m 48 CHEMISTRY FOR HIGH SCHOOLS. 3. If 15 litres of marsh gas be mixed with an equal volume of oxygen, and if the mixture be exploded at ordinary tem- peratures, what gas, and what volume of it will remain ; and what gas, and what volume of it will be produced ? Ans. 7*5 litres of CH^ : and 7'5 litres of CO3. 4. What volume will 48 grams of marsh gas occupy ? Ans. 67 "2 litres. 5. 70 litres of marsh gas are burnt in air, what weight and volume of carbon dioxide will be produced ? Ans. 70 litres, or 137*5 grams. Acetylenef G^H^', molecular weight j 26 ; specific weighty 13 ; 11*2 litres weigh 13 grama. Preparation : 1. Is formed by the direct union of carbon and hydrogen at a very high temperature. 2. By the incomplete combustion of many organic substances, as coal gas, &c. PropertiOS: Colorless gas, bums with a bright luminous flame, has a peculiar disagreeable smell, noticeable when a candle burns with a smoky flame ; poisonous ; forms explosive compounds with some metals, as potassium. Tests : Pass the gas through an ammoniacal solution of a cuprous salt, and a dark blood-red precipitate will be formed. . Ethylene (Ethene. Olefiant gas. Heavy coArhuretted hydrogen), C^H^; molecular weighty 28 ; spec^fi^c weight, 14. 11*2 litres weigh 14 grams. It is called ol^fiant^ because it unites with chlorine I ual volume linary tern- main ; and ? of COa. apy? •2 litres. freight and 5 grams. ic weight, rbon and Y organic m m ^1 W- ^m :Ci l>^ a bright ble smell, a smoky inds with 1 solution recipitate trburetted chlorine i; ® ■ i H 1' 1 mil i' ! ^pi'< , ii ', Hi' .iii' III;' \ |^|! ^iHCflf' > ' H ' iffiii' >''' erime]ltS ^th the cone of non-combustion : 1. Convey the gases in a small glass tube to a dis^ tance from the flame, and burn them. 2. Press a piece of wire gauze down upon the flame, and note its appearance when vie wed from above. Experiments relating to the light-giving part of flame : 1. ipold a piece of proce^ain over a candle flame.. It becomes covered with soot or finely divided, carbon. 2. Supply finely divided particles of iron or char- coal to the flame of a spirit lamp. Tho^ ^eat-giving part of the flame b<«comes quite luminous. 3. Show a Bunsen's lamp burning, first with its air holes closed, and then with them open. ^1 ■I if u CHEMISTRY FOR HIGH SCHOOLS. - 4. Hold a spiral piece of platinum wire in the flame of a Bunsen's lamp. The flame then gives much light. 6. Exhibit the Drummond light, and the oxy-hydro- gen lime light. 6. Burn a piece of magnesium wire. • These experiments prove that the light of a flame is caused by the incandescent particles of some solid substance contained in the flame itself, or aflected by it. When too much oxygen or air is supplied to a flame giving a uniform light, the efiect ib bo diminish its lighting power, by causing a more perfect combus- tion of the particles of carbon. If a flame is smoky, it is evident that carbon is greatly in excess, and that more oxygen is required for its combustion. In practice, the supply of air or oxygen to our lamps is increased by using a chimney. HALOGENS. This is the name given to four elements, Chlorine, Bromine, Iodine and Flourine, all having relations to each other that mark them ofi* as members of the same group or family of elements. CHLORINE. •Chlorine: Symbol, CI; atotaic weight, S5'6 ; molecida/r weight, Cl^, 71 ; specific weighty 35*5. 11*2 litres weigh 36*5 gra/ms. ^Sources : Is never found uncombined, and, generally the flame len gives xy-hydro- f a flame )me solid affected lied to a diminish combiis- s smoky, and that on. In lamps is 'Chlorine, ktions to s of the lohcfula/r I •£ litres enerally HI t.f! I ' \ % 't t ''il * r CHEMISTRY FOR HIGH SCHOOLS. 55 obtained from the abundant and well known com. pound sodic chloride, or common salt. Preparation : 1. Gently heat a mixin^tre of manganese dioxide, sulphuric acid and salt, in a glass retort. The reaction is thus represented : MnOa + 2 NaCl + 3 U^O^ = MnSO^ + 2 NaHSO* + 2 HP + C^. 2. MnOa + 4 HCl = 2 H2O + MnClg + Clj. Experiments : 1. Pass chlorine into water colored with indigo, or litmus. 2. Bleach moistened calico. 3. Explode a mixture of equal volumes of hydrogen and chlorine by sunlight. 3. Pour some powdered antimony, or bismuth, into ajar of the gas. Properties : Is a greenish yellow gas, with a suffo- cating smell ; cannot be collected over water or mercuiy, as it dissolves in the former, and combines wi^ the latter; it decomposes water giving off oxygen. Copper leaf, powdered bismuth, powdered antimony, and many other metals will bum brilli- . antly in chlorine gas, forming chlorides. It is a splendid disinfectant, and bleaches animal and vegetable colors by removing hydrogen from water, ' the liberated oxygen helping to destroy the coloring matter. i:;!-^ 56 CHEMISTRY FOR HIGH SCHOOLS. Tests : Its characteristic color and smell, and its spontaneous union with phosphorus and hydrogen. EXERCISE. 1. How much chlorine by weight and volnme can be obtained from 1460 grams of hydric chloride ? Ans. 710 grams ; 224 litres. 2. How much chlorine can be liberated from 685 grams of common salt ? What volume will it occupy ? Ans. 355 grams ; 112 litres. 3. What volume will 284 grams of it occupy ? Ans. 89*6 litres. 4. What quantities of manganic sulphate, hydro-sodic sul- phate, water, and chlorine, will be formed by the decompo- sition of 351 grams of common salt, with manganese dioxide and sulphuric acid ? Ans. 453, 720, 108, 213 grams respectively. 5. If 142 grams of chlorine gas be passed into steam, what substances wiU be formed, and what weight and volume of each? Ans. 146 grams, or 89 '6 litres of hydric chloride ; and 32 grams, or 22*4 litres of oxygen. 6. What weight of hydric chloride will 261 grams of manganese dioxide require for its decomposition ? Ans. 438 grams. COMPOUNDS OF CHLORINE. HydrocMoric Acid (" Spirit of salt ") : Forrmda^ HCl; molecular weight, 36'5 ; specific weight, 18*26. 11*2 litres weigh 18 J grams. It is frequently called muriatic acid. The commer* cial acid is usually of a yellowish color, and consists of water thoroughly impregnated with the acid gas; 1, and its hydrogen. ne can be ^ litres. 35 grams of 12 litres. ^'6 Utres. o-sodic sul- B decompo- ese dioxide ectively. earn, what volume of 3 chloride ; at oxygen. grams of ) grams. j/a, ffCl; t, 18-25. commeiv i consists acid gas; ^ i>^ (^5 CHEMISTRY FOB HIGH SCHOOLS. 57 Forms chloridoa with metals or their oxides. Its salts are termed haloid salts. Preparation : 1. Equal volumes of H and CI in direct sunlight unite with a powerful explosion forming this acid. Thus : H2 + CI2 = 2 HCl. 2. Generally prepared by heating a mixture of common salt and " oil of vitriol :" NaCl + HaSO* = NaHSO^ + HCl. Experiments : 1. Pass the gas into H2O coloured with litmus. 2. Bring the gas into contact with liquor ammonise. Explain the cause of the white fumes that are produced. 3. Show that it cannot be collected over water. Properties : It is a transparent and colorless gas, with a pungent smell and intensely acid taste ; is not inflammable ; is soluble in water to the extent of 480 times its own volume, producing a power- fully acid solution ; may be liquefied ; forms copious white fumes as it escapes into air. ^jj^ Tests : Its irritating smell, its incombustibility, its solubility in -v^ater. It forms a white precipitate with nitrate of silver. EXERCISE. The prineiple of atomicity nmy be employed in forming the chlorides of the metals, by taking one molecule of hydrio 58 CHEMISTRY FOR HIGH SCHOOLS. chloride as a type, and substituting for its atom of hydrogen a monad metal. One atom of a dyad metal must be substi- tuted for two atoms of hydrogen in two molecules of hydric chloride to form the chloride of a dyad metal, and so on with triads, tetrads, &c. There are important exceptions to this application of the principle. Type. Chloride. Name. HCl NaOl Sodic chloride. 2 HOI CaOla Calcic chloride. 1. Apply this principle and form the chlorides of the fol- lowing metals : Arsenic, gold, tin, manganese, iron, potassium, mercury, silver, zinc, calcium. 2. Name the compounds thus formed. Note.— Th« compounds which chlorine forms wltb metals ai-e often termed haloid salts, on account of their resemblance to other chemical salts. EXERCISE. 1. If 8 litres of hydrogen be mixed with 11 of chlorine, and the mixture be placed in sunlight, what substance will be formed, and what volume of it in the gaseous condition ? Ans. 16 vols, of HCl ; 3 vols of CI will remain. 2. What weight of common salt and sulphuric acid must be taken if it be required to eliminate 146 grams of hydric ohlAlde ? Ans. 234 grams of NaCl ; 392 of HaSO^. 3. Calculate the amount of hydro-sodic sulphate that will be produced in generating 219 grams of hydric chloride from salt and sulphuric acid at a moderate temperature ? Ans. 720 grams. 4. How many volumes of chlorine can be obtained from 20 litres of hydrochloric acid gf^ ? Ans. 10 litres. [>f hydrogen t be substi- Bs of hydric i so on with aonsto this ride, ride. of the fol- i, mercury. als are often her chemical ►f chlorine, •stance will condition ? i remain. acid must of hydric > that will oride from ? grams. ed from 20 litres. H CHEMISTRY FOR HIQH SCHOOLS. 69 6. What volume will 73 grains of hydrio chloride occtipy- at the standard temperature and pressure ? Ans. 44*8 litres. 6. What is the percentage composition of the gas ? Ans. 2-74 of H, and 97 26 of CL 7. Calculate the weight and volume of hydric chloride that can be formed by heating to a moderate temperature 409 '5 grams of common salt and 686 grams of sulphuric acid? Ans. 255*5 grams or 156*8 litres. CHLORINE AND OXYGEN. Oxygen forms with chlorine three well known oxides, and two hypothetical ones. Formula. Name. CORRBSPONDINO AOID. ClaO. 01,0,. Hypochlorous anhydride. Chlorous anydride. HCIO Hypochlorous acid. HClOa Chlorous acid. ClaO*. Chloric peroxide. No corresponding acid. ClaO.. Not eliminated. HCIO, Chloric acid. 01,0,. Not eliminated. HCIO4 Perchloric acid. All the compounds of oxygen and chlorine are un- stable, and most of them are explosive. Bleaching Powder is a mixture of calcic chloride and hypochlorite of lime. It is commonly called ** chloride of lime,'' and is formed by passing chlorine gas into a chamber containing slaked lime spread on large trays. ' :r, ^0 CHEMISTRY FOR HIGH SCHOOLS. 2 Ca (H0)2 + 2 OI2 = CaCla + Ca (C10)2 + H^O. Bleaching powder, as its name indicates, is used for bleaching purposes. A solution of the powder in water is filtered, and any article which it is desirable to bleach is soaked in the solution, and then in a very dilute solution of sulphuric acid. Chlorine is at once liberated, and uniting with the hydrogen of water, liberates the oxygen which destroys the color- ing matter. Chloric acid, HCIO3, is not of itself an important oompound, but its salts are important,' especially the one known as potassic chlorate. PotassiC chlorate, KCIO3, is prepared by pass- ing chlorine gas into a hot solution of caustic potash. The process of forming it may be symbolized as fol- lows • 6 KHO + 3 CI2 = 5 KCl 4- 3 H2O + KClOj. Chlorate of potash is a white crystalline solid, and is sparingly soluble in water. It is used extensively in the manufacture of fireworks and lucifer matches, and is the salt from which oxygen gas is most con- veniently obtained. SULPHUR. Sulphj/r : Symbolf S ; atomic weight, 32 ; melting pointy T15° ; boiling point j 446°. Sources > Old name, " brimstor. ; " found free in volcanic countries ; also combined with metals, as sulphides, for example, galena, blende, iron pyrites. HA 1 used for owder in desirable in a very le is at rogen of he color- nportant ially the by pass- 3 potash. 1 as fol- IO3. lid, and ensively natches, ost con- nelting tree in itals, as pyrites. \ I Prepa 1. Ri 2. Tl Prope wate flam( diffei matt Uses: pow( It fi phurou both oi Svlph\ Prep 1. ' 2. \ OHEMISTBT FOR HIGH SCHOOLS. 61 Preparation : 1. RoU sulphur is obtained by pouring melted sul- phur into wooden moulds of a cylindrical form. 2. The Jlowers of sulphur is produced by condensing sulphur vapor upon the walls and floor of a large, cool room, into which the vapor is passed from a large furnace in which the ore is roasted. Properties : is yellow, brittle, solid, insoluble in water, but very inflammable, burning with a blue flame ; is diniorphoUS, that is, crystallizes in two diflerent forms ; generally purified from earthy mattera by distillation. Uses : Sulphur is used in making matches and gun- powder. It forms two compounds with oxygen, viz. : sul- phurous anhydride, SO2, and sulphuric anhydride, SO3, both of which, when janited with water, form acids. COMPOUNDS OF SULPHUR. Stdphuroua Anhydride (Sulphnr dioxide) : Formulaf SO2 ; molecular weighty 64 ; density, 32. Preparation : 1. This substance is produced whenever sulphur is burned in air, or in oxygen gas. 2. Sulphur dioxide is usually obtained as follows : 2 H2SO4 + Ou = CUSO4 + 2 H2O + SOa 6 62 CHEMISTRY FOR HIGH SCHOOLS. It is used for bleaching articles that would be ruined if CI were used. Chlorine destroys the color- ing matter, SOj does not. The latter bleaches by removing oxygen. Experiments : 1. Place a -lighted taper in the gas. It is ex- tinguished. 2. Pass the gas into an infusion of litmus. 3. Pour the gas downwards upon a lighted taper placed in the bottom of a jar. 4. Show its solubility in HgO, and the subsequent acidity of the water. Properties : It is colorless, transparent, not inflam mable, and has a pungent, suffocating odor. It forms, with water, sulphurous acid. Thus : Tests : Its weight, smell, acid properties when united with water, and its bleaching pfoperties. Sulphuric Acid : Formula, H^^SO^ ; molecular weight. 98 ; specific gravity of liquid, I '8 46. This is the most important of all the acids, and the most extensively used in our manufactures. Preparation : 1. Nordhau8en Sulphuric Acid is made by the distillation of dried sulphate of iron (green vitriol). be ruined the color- • bleaches t is ex- ed taper bsequent ' inflam- ^or. It n united • weight. and the by the (green CHBMI8TKT FOR HIGH SCHOOLS. 63 2. The great bulk of the acid of commerce is manu- factured as follows : Sulphurous anhydride, steam, air, and nitric oxide, are passed into an immense chamber. " The nitric oxide in presence of oxygen im- mediately becomes nitrogen peroxide, and this, when mixed with sulphurous anhydride and a large quantity of water, furnishes sulphuric acid and nitric oxide. The sulphuric acid re- mains dissolvea in the water, while the nitric oxide, by absorbing oxygen from the air, again becomes nitrogen peroxide ; this combines with fresh sulphurous anhydride, which, when acted on by water, becomes sulphuric acid, the nitric oxide being again liberated, to go through the same series of changes with fresh portions of oxygen and sulphurous anhydride as long as any remain in presence of each other uncombined : NO2 + SO2 + xK^O = NO + (ar-1) H^O + HjSO*." This acid gives rise to a large class of salts called sulphates. It one atom of hydrogen, in the molecule of H2SO4; be replaced by one atom of a monad* metal, there is formed what is called an Acid sulphate ; if all the hydrogen be replaced by a metal, a Normal or Neutral sulphate. Properties : The oil of vitriol of commerce is a dense oily-looking colorless liquid, without odor, is in- m i:'i 64 CHEMISTRY FOR HIGH SCHOOLS. tensely caustic, and chains almost all organic sub: stances, "owing to its powerful attraction for moisture." Test : Baric chloride gives with sulphuric acid, or any soluble sulphate, a white precipitate insoluble in all acids. Sulphuric acid chars organic compounds. Hydric Sulphide {Sulphuretted hydrogen) : Formulaj H^ ; molecular a)ei(/ht, 34 ; specific weighty 17. 11*2 litres weigh 17 grams. Sources : Is found free in volcanic countries, and also dissolved in spring water. Also called Hydro sulphuric acid. Preparation : 1. Ferrous sulphide treated with dilute sulphuric acid. Thus : FeS + H2SO4 = FeSO^ + H S. 2. By treating antimony sulphide with hydroch- loric acid : Sb2S3,+ 6 HCl = 2 SbClg + 3 HgS. Experiments : 1 . A- jet of the gas burns wi^ a blue flame. 2. Explode a mixture of 2 vols, of HjS with 3 vols, of O. 3. Pass a stream of the gas into solutions of cupric sulphate, ferrous sulphate, zinc sulphate, and acetate of lead, and observe the effects. nic sub: iion for acid, or nsoluble I pounds. \ 17. ies, and 1 Hydro ilphuric ydrocli- with 3 ' cupric ite, and /^* ■i' Bl'.^i CHEMISTRY FOR HIGH SCHOOLS. 65 PtTOportiOS : Is a colorless, transparent and poisonous gas, with the odor of rotten eggs. Soluble in water to about the extent of 4^ times its own volume ; and burns with a blue flame. It has an acid reaction. Test I It blackens acetate of lead paper. This, with its smell, distinguishes it from all other gases. EXERCISE. 1. Calculate the percentage composition of sulphur dioxide. Anr. 50 of and 50 of S. 2. What volume will 112 grams of sulphur dioxide occupy ? Ans. 39-2 litres. 3. Find the weight and volume of sulphur dioxide that can be obtained from 588 grams of sulphuric acid and 10 lbs. of copper. Ans. 192 grams; 67*2 litres. 4. If sulphur trioxide be passed through a tube heated to a high temperature it breaks up into sulphur dioxide and oxygen gas. Find how much oxygen can be obtained in this way from 320 grams of ^sulphur trioxide. Ans. 48 grams ; 33*6 litres. 5. How many litres of sulphur dioxide must be dissolved in water to produce 410 grams of sulphurous acid. Ans. 10 litres. 6. If 48 grams of sulphur be completely oxidized in presence of vapor of water, what compound, and what weight of it, will be produced ? Ans. 147 grams of HaS04. 7. Every volume of sulphuretted hydrogen requires for its combustion one and a half volumes of oxygen ; what compound and what weight of it will be formed by the combustion of 78*4 litres of this gas ? Ans. 287 grams of H,SO,. 66 CHEMISTRY FOR HIGH SCHOOLS. 8. How much sulphide of iron and sulphuric acid must be used to evolve 89*6 litres of sulphuretted hydrogen? Ans. 352 grams ; and 392 grams respectively. COMPOUND OF CARBON AND SULPHUR. Carbon disulphide {Carbonic aulphidey sulphocarbonic a>cid) : Formnfa, CS^ ; molecular weighty 76 ; specific weight of vapor, 38. Preparation : This substance is formed by passing sulphur vapor over red hot charcoal and condensing the product. The chemical equation is : 2 S2 + C2 = 2 CS2. Experiments : 1. Dissolve a piece of P in CS2. Then dip a piece of paper in the solution, and allow it to dry upon an iron frame. Spontaneous combustion takes place. 2. Ignite a few drops of the liquid. • Properties : It is a very volatije liquid with a disagreeable smell ; it is heavy, transparent, and colorless ; does not mix with water ; it boils at 4 3*^C, and when its vapor is mixed with oxygen, the mixture becomes explosive. Its combustion in air produces carbon dioxide, and sulphur dioxide. It readily dissolves resins, phosphorus, iodine, sulphur, and india-rubber. Uses : It is used extensively in the arts, especially in the vulcanization of caoutchouc, and in the manufacture of gutta-percha. d must be sctively. UR. ocarbonic ; specific J passing ndensing p a piece t to dry nbiistion with a ent, and at 4 3=0, »en, the >n in air ide. It sulphur, ipecially in the m W \\ ■ ' '1,1 I fk i ' I CHEMISTRY FOR HIGH SCHOOLS. 67 PHOSPHORUS. Phosphorus : Symholy P; atomic weighty 31 ; moleciUttr weight, 1 24 ; specific weight in gaseotis state, 62. Sources : Phosphorus is never found uncombined in nature. By far the greater part of the bones of animals is made up of phosphate of lime. Indeed calcined bones were for many years the chief scarce of this element. At present it is largely obtained from mineral phosphates. Preparation : Treat bone-earth or the mineral phos- phate of lime with dilute sulphuric acid, and there will be formed an insoluble calcic f'ulphate and superphosphate of lime. Thus : Gas (PO^)^ + 2 H2SO, = 2 CaSO^ + CaH^ (PO*)^ Filter the product, a nd throw away the insoluble sul- phate. Then evaporate the solution to dryness, mix the residue with charcoal, and distil in an earthen retort. Carbonic oxide will be formed ; and phos- phorus vapor will pass over, and may be condensed under water. This reaction may be thus represented : 3 CaH,(P04)2 + do = Ca8(P04)2 + 6 HjO + 10 00 + P^. Phosphorus exists in two well-known forms : 1. As yellow phosphorus. 2. As red or amorphous phosphorus. The yellow variety is obtained as outlined above, but requires some further purification. The red is formed by heating yellow phophorus, ^in an atmos- m m m m 68 CHEMISTRY FOR HIGH SCHOOLS. phere from which oxygen is excluded, to a temperature of about 240°C. , Properties : The properties of the two varieties of this element may be contrasted as follows : Yellow. Red. Poisonous. Innocuous. Strong odor. Nearly odorless. Phosphorescent. Not phosphorescent. Melts at 44''C. Melts above 260°C. Transparent. Opaque. Soluble in various liquids. Almost insoluble. Soft. Hard as brick. Crystalline. Amorphous. Must be kept under water. Bemains unchanged in. air. Uses : This element is extensively used in the manu- facture of lucifer matches. A paste is made of phosphorus, potassic chlorate, glue and powdered sand, and the ends of the matches are tipped with it. The " safety" match is tipped with a paste of potassic chlorate and antimonious sulphide, and the " rubber," upon which it has to be rubbed before it ignites, is made of red phosphorus and antimonious sulphide. The ordinary match, as well as the ** safety " one I oaperature arieties of mt. C. [edii^air. he manii- made of powdered ped with a. paste of », and the I before it :imoiiious ety" one CHEMISTRY FOR HIGH SCHOOLS. 69 ignites by friction. The rubbing generates sufficient heat to cause the phosphoi-us to take fire, and when once ignited the combustion is supported by the oxygen supplied by the potassic chlorate. EXERCISE. 1. What weight of phosphorus can be obtained from 1053 grams of superphosphate of lime ? Aks. 186 grams. 2. How much sulphuric acid will be required for the de- composition of 62 grams of calcic phosphate ? How much superphosphate of lime will be produced in the process ? Ans. 39 '2 ; and 46*8 grams. 3. In question (2) calculate what weight of phosphorus would be produced, and what volume it would occupy, if it could exist in the gaseous condition at the standard tempera- ture and pressure. Ans. 8^26 grams ; 1.5 litres nearly. COMPOUNDS OF PHOSPHORUS. Phosphorus and oxygen form two well-known com- pounds : Name. Phosphorus trioxide. rhosphoruB pentoxide. FORMCLA. P.Os. PaO,. CuRRESPoNcmo Acids. H^POg Phosphorous acid. ' H.PO4 Orthophosphoric acid. HPOa Metapbosphoric acid. H4P3O, Pyrophosphoric acid. Phosphorus trioxide, or phosphorus oxide, is formed by burning phosphorus in a limited supply of m 70 CHEMISTRY FOR HIGH SCHOOLS. air. Obtained in this way it presents the appearance of a white powder. Phosphorus PentOXide, or phosphoric oxide, is produced as white fumes under a bell jar when phosphorus is burned in a copious supply of dry air, or oxygen gas. These fumes soon settle as a snow white powder, which, when exposed to the air for a few minutes, deliquesces to a liquid. It has an intense affinity for water, with which it unites to form, in the first place, probably, metaphosphoric acid, HPO3. Thus : PA + H2O = 2 HPO3. If the solution represented by the formula HPO3 be boiled in Water for soiive time, orthophosphoric acid is formed. Metaphosphoric acid is often called '* glacial phosphoric acid." Orthophosphoric acid, H3PO4. This substance can be prepared by carefully heating small pieces of phosphorus in dilute nitric acid. The nitric acid oxidizes the phosphorus, and glacial pl^os- phoric uUd is formed. This, as stated above, when heated with water takes up another molecule of water and forms orthophosphoric acid. This substance, H3PO4, is interesting as illustmting what is called a tri-basic acid ; that is, an acid which is, capable of forming three kinds of salts, according as one, two, or three of its hydrogen atoms are replaced by one, two, or three atoms of a monad metal. For Axampie : . ppearance tic oxide, jar when f dry air, & a snow ! air for a m intense fm, in the c acid, la HPO3 loric acid n called r heating 5id. The ial pIjLOs- ^By when of water ibstance, called a pable of two, or ne, two, pie: 1 * 2. CHEMISTRY FOR HIGH SCHOOLS. 71 NaH^PO^ is called dihydro sodic phosphate. Na2HP04 is called hydro disodic phosphate. Na3P04 is called trisodic phosphate. • ' The basicity of an acid, therefore, depends upon, the number of exchangeable atoms of hydrogen which its molecule contains. Nitric acid, HNO3 is mono- basic ; sulphuric acid is bi-basic. COMPOUND OF PHOSPHORUS AND HYDROGEN. Phosphoretted hydrogen (Phoaphine) : Formukif PH ; molecvlar weighty 34 j specific weighty 17. 11*2 litres weigh 17 gra/ma. Preparation : 1 . Heat phosphorus acid in a small retort : 4 H3P03=3 H3PO4 + PH3. 2. Boil some small pieces of phosphorus in a solu-> tion of sodic hydrate, or of slaked lime. Reaction : P4 + 3 H2O + 3 KH0=3 K2HPO2 + PH3. Experiments: 1. Carefully allow bubbles of the gas to escape into* air. Spontaneous combustion results, and a beautifnl'ring of white smoke is produced. 2. Keep a quantity of the gas over water for a few. days. 'I i , tfl" !t, ii ■ ;j 72 CHEMISTRY FOB HIGH SCHOOLS. Properties: When prepared by the first of the above methods the gas is not spontaneously inflam- mable. It possesses a strong offensive odor, like garlic ; is* slightly soluble in water ; and burns with a brilliant white flame. It is analogous to ammonia in some of its chemical relations. Its combustion may be symbolized as follows : =H3P0,. Test : Its flame ; its odor ; and its spontaneous in- flammability when prepared by the second of tlie above methods. The gas loses this property when kept standing over water for some time. PH3 + 2 O2 EXERCISE. 1. What weight and volume of phosphine can be obtained from 41 grams of phosphorous acid ? Ans. 4*25 grams ; 2*8 litres. 2. What volume will 51 grams of the gas occupy ? Ans. 3^-6 litres. 3. If 28 litres of phosphoretted hydrogen be decomposed into its constituent elements, what volume will they occupy in the gaseous condition at the standard temperature and pressure ? A. 4 litres of P ; and 24 of H. 3. If 56 litres of phosphine be burned in oxygen, what •compound and what weight of it will be produced ? Ans. 225 grams of HaPO*. 5. What weight of metaphosphoric acid can be formed from .38*5 grams of phosphorous pentoxide ? An». 40 grams. first of the isly inflam- odor, like and biirns aalogous to itions. Its I : itaneous in- lond of tlie perty when ; be obtained 2-8 litres. py? 3^-6 litres. decomposed they occupy perature and d 24 of H. xygen, what L? of HaPO^. formed from grams. ih \W What ing nain< 1. Ar 2. Ch 3. Ar 4. Po 5. Ep m Asul composi 47-02 ; 1 To 80 ing rule 1. 2>i byUsm 2. D tJiem. S. Ri and the each ek Ins I i C CHEMISTRY FOR HIGH SCHOOLS. 73- EXERCISE. What is the percentage composition of each of the follow- ing named substances : 1. Arsenious oxide, AS3O3. Ans. 75-75 arsenic ; 24*25 oxygen. 2. Chloride of gold, AuClg. Ans. 3514 gold; 64 86 < hlorine. 3. Arseniuretted hydrogen, AsHg. Ans. 96*15 arsenic ; 3*85 hydrogen. 4. Potassium ferrocyanide, K4, FeCeN,. Ans. 42 -45 potassium ; 16*2 iron ; 19*55 carbon ;. 22*8 nitrogen. 5. Epsom salts, MgS04. Ans. 20 magnesium ; 26*67 sulphur ; 53*33 oxygen. EMPIRICAL FORMULAE. A substance upon analysis yields the following percentage* composition : Potassium, 28*73 ; hydrogen, 0*73 ; oxygon, 47*02; sulphur, 23*52. Calculate its empirical formula. To solve this and all similar problems observe the follow- ing rule : 1. Divide the percentage amount of each constituent ekment by its own atomic weight. 2. Divide each of the quotients thus obtained by the lowest of tJiem. 3. Reduce the second set of quotients to their Amplest ratios, and the numbers obtained will express the number of atoms of each element in the compound. In solving the above question proceed as follows ; Potassium 28*73 -f 39*1 = -73 Hydrogen -73^ 1 = -73 Oxygen 47*02 -r 16 = 2-93 Sulphur 23-52 ^ 32 = -73 74 CHEMISTRY FOR HIGH SCHOOLS. Now the smallest of these quotients is '73, and dividing each of them by this, we obtain one for K, one for H, one for S, and four for 0. The empirical formula is, therefore, KHSO4, and the substance in hydropotassic sulphate. The problems in the following exercise can all be solved in a similar manner. EXERCISE. Calculate the empirical formula and name the substances which yield upon analysis the following percentages of the elements named. 1. Carbon, 42*86 ; oxygen, 57*14. Ans. CO, carbon monoxide. 2. Hydrogen, 2-73 . chlorine, 97.27. Ans. HCl, hydric chloride. 3. Hydrogen, 83 ; sodium, 19.17 ; sulphur, 20*66 ; oxygen, ■53*33 Ans. HNaS04 hydro sodic sulphate. 4. Sodium, 39*31 ; chlorine, 60*69. Ans. NaCl, sodic chloride. 5. Nitrogen, 82*35 ; hydrogen, 17*65. Ans,. NHg, ammonia. 6. Phosphorus, 91*17 ; hydrogen, 883. Ans. PH,, phosphine. 7. Carbon, 26*67 ; hydrogen, 2*22; oxygen, 71*11. Ans. CjH^O^, oxalic acid. 8. Carbon, 75 ; Hydrogen, 25. Ans. CH4, marsh gas. 9. Carbon, 12 ; calcium, 40 ; oxygen, 48. Ans. CaCO,, calcic carbonate. •73, and •ne for K, empirical bstance is can all be > substances iages of the pionoxide. : chloride. >6 ; oxygen, sulphate. ' chloride, ammonia. hosj)hine. •11. :alic acid. larsh gas. arbonate. CHEMtSTRT FOR HIGH SCHOOLS. 75 MISCELLANEOUS EXERCISE. L 30 litres of hydrogen are mixed in a flask with 20 litres of oxygen. Which gas remains in excess after explosion, and how many litres of steam are produced ? AnB. 5 litres remain ; 30 litres of steam. 2. Mix 10 litres of hydrogen with 15 of chlorine, and calculate the total volume of the gases after explosion. Ans. 20 litres HCl ; 5 litres of CI. 3. A certain volume of sulphuretted hydrogen required for its combustion 75 litres of oxygen. Find that volume, and also the weight of the substance produced. Ans. 50 ; and 183 grams of H3SO,. 4. Assuming that ^ the volume of air is oxygen, calculate bow many litres of air it will take to burn 20 litres of (a) carbonic oxide, (h) phosphine, (c) defiant gas. Ans. 50 ; 200 ; and 300 litres respectively. 5. If 10 volumes of carbon dioxide be passed over red hot charcoal, what gas and how many volumes of it will be formed ? Ans. 20 vols, of 00. 6. 25 volumes of steam are passed into a tube containing red hot iron filings, what gas will pass out, and how many volumes of it ? Ans. 25 vols of H. 7. A series of electric sparks passed into a 20 litre jar of ammonia gas decomposed it. Find the volume of the consti- tuent gases. Ans. 5 litres of N ; and 15 of H. \^ . 8. 24 grams of carbon are burned in oxygen gas. Find the volume of the gas produced. Ans. 44*8 litres. 9. 80 grams of sulphur are made to burn in 56 litres of nitrous oxide gas. Find the resulting volume of gas formed, and the volume (if any) of nitrous oxide remaining. Ans. 66 litres SO. formed : and 56 litres of N. i 76 CHEMISTRY FOR HIGH SCHOOLS. 10. How many litres of oxygen and nitrogen respectively can be obtained from 30 litres of nitrogen tetroxide? "Ans. lOof N ; 20 of 0. 11. How many cubic inches of hydrogen and nitrogen respectively can be obtained from one litre of ammonia gas ? Ans. 15-25 N ; and 4577 of H. 12i If 10 litres of oxygen be united with 5 of sulphur vapor, what will be the volume of the resulting compound gas at standard temperature and pressure. Ans. 10 litres. ispectively e? 20 of 0. 1 nitrogen nonia gas ? n of H. of sulphur compound 10 litres. ^ ■Mflf 'W« W: ffii F iff'l' ..Jil ;. This sal (1) QualJ of t con (2) Quan tioo bas< The firs far as all t somewhat equipped Thesul or in the exanuBei obtainabl are valua kind of i CHEMICAL ANALYSIS. This subject admits of a two-fold division, viz., into : (1) Qualitative Analysis, whose object is the discovery- of the metals, bases, and acids that compose a givenr compound. (2) Quantitative Analysis, whose aim is the determina- tion of the relative weights in which such metals,, bases and acids occur, in the given compound. mi The first operatioii is comparatively easy, especially in so- far as all the common metals are concerned ; the second is^ somewhat difficult, and can only be carried on in a well- equipped laboratory, if strictly reliable results are desired. PRELIMINARY OPERATION. The substance presented for analysis may be in the solid,, or in the liquid form. If solid, the student may begin to examine it as follows, simply remembering that the results' obtainable in this way are not trustworthy, but that they are valuable because they often furnish hints regarding th& kind of ingredients composing the analytical specimen. 6 11' 78 CHEMICAL ANALYSIS. Urn ,5 *"5 » C^ s .2 9 , e « . Ai .5 00 * " O 00 e ca.S a S3 ^ a >t ■S oJ * b •^ f > n '3 d o o I IS a a & o 05 I Pow of it:- (1)1 (2)] (3)] Note. calanal No¥ four h such si called tests, I.- IL- III.- ' IV.- 1 Th class] divid 1. 1 CHEMICAL ANALYSIS. 79 SECOND OPERATION. Powder a piece of the assay and prepare three solutions of it :— (1) By boiling in distilled water. (2) By boiling in hydrochloric acid. (3) By boiling in nitric acid, or in aqua regia. , Note. — If no solution can be obtained, a more advanced work on chemi- cal analysis must be consulted. Now all solutions of metals and bases may be arranged into four large classes or groups, by the efifects produced upon such solutions by treating them with certain other solutions, called group re-agents. The usual group re-agents, or group tests, as they are sometimes called, are the following : — I. — Sulphuretted hydrogen added to an acid solution of the assay. IL — ^Ammonium sulphide to an alkaline solution — ammonia being first added to insure alkalinity, and ammonium chloride to prevent the precipitation of magnesium compounds. III. — Hydro di-sodic phosphate to an alkaline or neutral solution — ammonia and ammonium chloride having been previously added. IV, — ^The test for this group is the absence of any precipi- tate through the agency of any of the preceding re-agents. FAMILIES. These four groups of metals or bases may be further classified into families. For example. Group I. may be sub- divided as follows : — > 1. Family, precipitated white by HCl, the precipi- tate being permanent. Members : Ag, Pb, Hg (-ous that is, mercury as a sub-salt). 80 CHEMICAL ANALYSIS. 2. Family, precipitated yellow from a solution, acidified with HCl, by H.,8. Members : As. Sn(-ic) Cd. 3. Family, precipitated brown from the acidified solution, by HgS. Member : Sn, as a stannous compound. 4. Family, precipitated orange from acidified solu- tion by HjS. Member ; Sb. 5. Family, precipitated black from acidified solu- tion by HgS. Members : Pb, Hg, Cu, Bi, Au, Pt. The three solutions, prepared as directed above, should each be treated by the group re-agents. As s on as the group to which the base or metal belongs has been deter- mined, the family and the individual element can easily be made out, by applying the proper tests. The operations indicated above may be tabulated as follows : — a solution, the acidified i. cidified solu- sidified solu- bove, should s on as the been deter- can easily be tabulated as n'i>\ m •3D § ''^ H t-H o O c^ < f*": CHEMICAL ANALYSIS. 81 i-i :^ ■3D ♦H I H O I o I ^ a I OB « .5 .a AQQ 'Ifc cq e -7 I Red solution .... Ft :p ^ c^-i S ^ I Purple ppt Au o ^ OS ■ ■ l^i S S White ppt Bl ta§ —z Sg^ !g Blue solution.... Cu 5 8 e pa Yellow ppt Hg(ic) .2 W :g ^ S o o 'S' BO White ppt Pb W ^Sil sb «52a Sn(-ou8) 09 04 1^1 ^ ^'s a o -o « Ph eh Ppt. forms & remains .. Cd Ppt. forms & dissolves .. Sn(-ic) ^«1o As (-ic) Hill Eoa ppt. •11 i "'^ e£;i »S| Yellow ppfc...A8(-ous) Denotes separated sulphur. * § a '3 M < (b) Remains. To the original add KHO Gree nish. Red dish. Bh le. On sen. A 1 Zi 1. Mn Or F eO Feg Oa C D N i families as alkaline so- ' NH^HS. HS. HS. mbers of the ffD ITS tate. l;i ire t5iy. 11 ate. (b) Remains. ro the original add KHO Bli le. Gk sen. C N n The th and consi fa) To origi White] Ba This g non-prec; group tec sists of o: CHEMICAL ANALYSIS. 8$ GROUP ni. The third group is not usually subdivided into families^ and consists of the following members : Mg, Ca, Sr, Bi . Analytical Table. Group III. AddNH4Cl, NHs, HNagPOi. Ppt. White. To original solution, add CaSO^ solution. fa) White precipitate. To original add H 2 Si Fe. White ppt. No ppt. Ba. Sr. (b) No pi*ecipitate. To original add oxalate of ammo- nia (NHO2O. White ppt. No ppt. Ca. Mg. OROUP IV. This group, as previously remarked, is characterized by non-precipitation through the agency of any of the preceding group tests. It is also not subdivided into families, and con- sists of only three members, viz., Na, K, and the radicle, NH^. Analytical Table. Group IV. Evaporate to dryness, and heat strongly. (a) Volatilizes. (b) Residue remains. NH4 Na or E. - These may be distinguished by the color they impart to flame; or better still, by the spectroscope. m 1 jfl 1. ■# EXAMINATION QUESTIONS. The following sets of questions Jiave been selected from the Ekmeatai'y Papers on Chemistry given at Queen\H College. I. 1. Describe carefully how the composition of water is de- termined synthetically and analytically. 2. Taking a molecule of water as a type, explain fully the composition of an acid, a base, and a salt ; give examples. What practical differences are there between these three compounds ? 3. What is meant by a substance in its nascent state and what are its properties ? Give cases in illustration. 4. Give all the chemical changes, where known, and any visible phenomena, when : — (a) zinc is put into sulphuric acid ; (6) copper is put into nitric acid under a bell jar ; (c) electric sparks are passed through air ; {d) potassic chlorate is acted on by hydrochloric acid ; (e) wood is heated in close vessels. 5. How would you determine the proportion of oxygen in the air ? How prove that it is not in combination ? 6. Explain the action going on in the several parts of a common flame. What is the effect of too little air upon it ? Of too much air ? 7. What volume of ammonia can be obtained from 100 grams of ammonic chloride. II. 1. Give] the length of a metre in inches, and show its relation to the gram and litre. )I, 1 86 EXAMINATION QUESTIONS. 2. How many times is the gas CI3O4 heavier than air ? Ans. 4-67. 3. Explain the meaning of the terminations, -ous, -ic, -ide» -ite, -ate. 4. (a) Show how to obtain nitric acid. (6) Given nitric acid and other necessaries obtain N^O, N3O3 and N3O3, giving formulae. 5. What gas and what weight of it will be obtained by acting on marble by 100 grams of HCl ? 6. Benzine burns with a smoky flame. Explain the cause of (a) the heat, (b) the light, (c) the smoke. How may the smoke' be prevented ? 7. Describe sulphuric acid and explain its formation. 8. If a molecule of water consists of 3 atoms, show that a molecule of hydrogen consists of 2. State Avogadro's law. / in. 1. Give general dilSTerences between chemical compoun Is and mechanical mixtures. 2. Upon what basis does Avogadro's law rest ? Shew how from it you can find the density of the gas CaHeO. 3. How would you distinguish certainly between : — Oxygen and nitrous oxide ; nitrogen and carbon dioxide ; hydrogen and carbon monoxide ; phosphine and arsine. 4. Show how to obtain liquor ammonise. Of what is it a hydrate ? 5. Describe Bunsen's burner, and explain its action. 6. You are given "salt," alcohol, manganic dioxide, and sulphuric acid. How will you obtain hydrochloric acid, chlorine, oxygen, olefiant gas ? ' »'-'»> f\ 7. 100 acid, and Whatwei TIte fol nat m 1. C ing dai of glol carbon preBBU 2. I of the EXAMINATION QUESTIONS. 87 7. 100 grains of oxalic acid is decomposed by sulphuric acid, and the escaping gases are passed through lime water. What weight of calcic carbonate will be formed ? Ass. 111} grams. IV. 1. If one volume each of the following gases be burned with oxygen, what gases, and what volume of each will be formed ? — marsh gas,,oletiant gas, phosphine, hydric sulphide. 2. Give the composition of the following, and state how they are obtained : — ozone, laughing gas, bleaching powder. 3. Give the principal constituents of the atmosphere, with their uses ; and show how the relative amounts of oxygen, carbon dioxide, and water- vapour may be obtained. 4. Give the reaction, and products when : — (a) zinc is put into hydrochloric acid ; (6) tin is acted upon by nitric acid. 5. What takes place when : — (a) magnesium is heated in air ; (b) ammonia is added to CuSO^. Solution. 6. When does a gas become a vapour, and vice versa? State their similarities and differences. Tlie following questions have been selected from the Exami- nation Papers of Toronto University for tfie years 1879^ 1880, and 1881. 18 7 9. I. 1. Calculate the density of carbon dioxide from the follow- ing data : — Weight of globe full of air, 948 grammes ; weight of globe exhausted, 933-6 grammes ; weight of globe full of carbon dioxide, 955*54 grammes ; assuming temperature and pressure to remain constant during the experiment. 2. Illustrate the laws of chemical combination by means of the compounds of nitrogen, with oxygen and hydrogen. 1 83 EXAMINATION QUESTIONS. 3. What is the usual source of nitric acid ? How is it pre- pared ? What weight of each of the mateiials must be taken to obtain 300 grammes nitric acid ? 4. What is meant by •* allotropism t' Illustrate with car- bon, sulphur, and any other element. 5. Give a full description, illustrated by a sketch of appa- ratus, of the method usually adopted in the laboratory for generating and collecting chlorine. How is liquid chlorine obtained? What are the more important properties of chlorine ? 6. What is ozone ? How formed ? What are its proper- ties ' 7. Peroxide of hydrogen. Give its preparation and pro- perties. How distinguished from ozone ? 8. What is meant by atomic weight ? How is the molecu- lar weight of a substance determined ? Give reasons for be- lieving that the molecule of the elements usually contains two or more atoms. 1880. I. 1. How may the following substances be shewn to be com- pounds of nitrogen: — Nitric acid ; ammonia; cyanogen? 2. Describe a process for the formation of sulphuri . acid. Calculate the percentage composition of copper suxphate. Cu = 63: 8 = 32:0=16. 3. Write equations expressing the action of sulphuric acid on each of the following substances : Sodium chloride ; sodium carbonate ; sodium nitrate ; copper. 4. Give the names and formulae of the principal compounds of phosphorus, and compare them with those of nitrogen. w is it pre- 3t be taken e with car- h of appa- sratory for id chlorine )perties of its proper- 1 and pro- lie molecu- lons for be- y contains to be com- nogen ? liun . acid. : sulphate. [)huric acid le ; sodium compounds itrogen. 5. St Whys] 6. D produc what c 1. S Whys •2. \ mixtu S. I into i carboi 4. ) Show 5. S confoi (Pb = 6. (a) n trioxi acid. 1. gravi 2. ohloi that EXAMINATION QUESTIONS. 89 6. State fully what facts are represented by the equati; ;i.vto che "ji jshitution ot" the compound ZnSO^ on the supy r oil iisat the combining equivalent of O = 100. 3. ir't a, '; u it thi'> relations existing between the oxygen and sulphur oonif-ouiKls. 4. Statt j>. properties of sulphur trioxide, and describe a method of preparing it. 5. Distinguish between chemical and physical changes. ur be pre- phur diox* disulphide. 1 gram of ions : — (a) tmmonium m nitrate. itly deter- 1) t and for- tf Victoria ' Professor id at 20°C ks through ? elements JO4 on the 100. tygen and lescribe a anges. C,4 er iiiust the action 7. Distil adhesion. 1.. Wha lecidar coi 2. Intl: gas dischs quires. ^ 3. Dem by Sir Hi of a cand 4. Stat tion : 5. Ho^ and 760 trioxide water, v 6. Ai through posing i mm. pr< mixture 7. Si3 Bufficiei decom] to weij sulphu and 78 EXAMINATION QUESTIONS. 91 6! Illustrate by an example the effect of insolubility upon the action of chemical affinity. 7. Distinguish between chemical affinity, cohesion and adhesion. II. 1., What are the grounds for the assumption of the mo- lecular constitution of the elementary gases. 2. In the electric decomposition of water the volume of gas discharged at the positive pole is less than theory re- quires. Why ? 3. Demonstrate the incorrectness of the explanation offered by Sir Humphrey Davy for the luminosity of the middle layer of a candle flame. 4. State fully the facts symbolized by the following equa- tion : (NO)2+02=(N02)2. 5. How much by volume of SO 2 and measured at lfi°0 and 760 mm. pressure is required to furnish sufficient sulphur trioxide which, when combined with the proper amount of water, will form 32 grams of Ha SO 4 ? 6. A mixture of oxygen and ozone was allowed to bubble through 64 grams of hydrogen peroxide, completely decom- posing it, the resultant gas measured 90 litres at 4°C and 763 mm. pressure. How much oxygen by weight did the original mixture contain ? 7- Sulphuretted hydrogen was allowed to act upon a sufficient quantity of sulphur dioxide, producing complete decomposition of the gases. The sulphur obtained was found to weigh 15 grams. How much by volume respectively of sulphuretted hydrogen and sulphur dioxide measured at 20°C and 780 mm. pressure entered into the reaction ? M 92 EXAMINATION QUESTIONS. m. 1. Reduce 25° Centigrade to Reaumur and to Fahrenheit, 2. State BerthoUet's law and illustrate by examples. 3. Illustrate the law of multiple proportions by examples. 4. Distinguish between the combining equivalent and the atomic weight of an element. * r>, State the properties of hydrogen and the modes of its preparation, illustrating the latter by diagrams of apparatus used, and representing the reactions taking place by equa' tions. 6. State the j-operties of nitrogen monoxide, the moet convenient mode ot its preparation, and prove its volumetric composition 'to be represented by NjO. 7. Solve the following questions : (M. ^h = 4Zn + 2 (HN08)+4 (H^SOJ = 9(HN08) + (HaO)x +4Zn = Cu + 2(H2SOJ = 8. How much On is required for the evolution of 75 litres of nitric oxide from HNO, -temp. = 40°C press. = 650 mm. ? Cu = 63-5. 9. A mixture of O and N when transferred to a Hofifman's Eudiometer measured 30 cc. After the adddition of H the volume was found to be 46*2 cc. After explosion by the electr^o spark the remaining volume measured 32 volumes. How much in weight was originally present in the mixture^ the temperature and preMurv") remaining constant at C'C and 760 mm. ? N.B. sentB, -In "working the examp^ state clearly wbat each quantity repre- 'ahrenheit. pl€s. examples, at and the • odes of its apparatus J by equa" i the most volumetric f 75 litres 5SS. = 660 Hofiman's of H the m by the volumes. i mixture^ -t O-^C and ntlty repre- D "> ' 1. De8( monium c prepared. ' these pro 2. Desi \ you have given 8p< found to ' which it 1 ! 3. Wh 1, nitric q: dioxide, ! 4. Dea given by ,' 5. Dei allotropi f is said t< 6, Ca] ) potassiu 7. W \' the rela molecul of the84 8. Oi potassii \ obtaine much BZAMINATION QUESTIONS. ^3 INTERMEDIATE EXAMINATION. JULY, 1880. 1. Describe the chief characters of (1) ammonia, (2) am- monium carbonate ; and the process by which they are usually prepared. Give also the chemical reactions which occur in these processes. 2. Describe fully the modes of decomposing water which you have seen. State how you would determine whether a given specimen of water is hard or soft. If the water is found to be hard, state (with reasons) the various means by which it could be made soft. 3. What means are best employed for the collection of nitric oxide, chlorine, ammonia, carbonic acid, sulphur dioxide, and nitrous oxide gases. 4. Describe fully the experiment in which the reactions are given by the equation. CaCO, + 2 HCl = CaCla + H,0 + CO,. 5. Describe some of the properties of sulphur, and state its allotropic modifications, and how they are obtained. Sulphur is said to be a dimorphous body — explain. 6. Calculate the percentage composition by weight of potassium nitrate, and of the two oxides of carbon. 7. Write down the atomic weight, the molecular weight, the relative weight, the specific gravity, the atomic and the molecular volume of chlorine, and fully explain the meaning of these terms. 8. On completely decomposing by heat a certain weight of potassium chlorate, 20 246 grains of potassium chloride was obtained. What weight of potassium was used, and how much oxygen was evolved ? IMAGE EVALUATION TEST TARGET (MT-3) , IS, sulphur at for this eated with much zinc >v.-'~y^ N 1. A s] part was portion, < finely «po^ found the portion r the cause 2. Hoi by burni 3. Wh upward t carbon d 4. Aq was igni gauze h( confined greater { State th< depends. 5. Asa a ohemi< and nitr 6. Dei in being 7. Wi place in by diagr ooUectio 8. A when p] Explain EXAMINATION QUESTIONS. 9ft JULY, i882. 1. A specimen of water was divided into two parts. One part was then boiled for some time. To this and the unboiled portion, contained in separate bottles, a small quantity of finely 'powdered chalk was added. Upon agitation it was found that the boiled portion had become milky, the unboiled portion remained clear, the chalk having dissolved. Explain the cause of this difference. 2. How much sulphur dioxide, by weight, can be obtained by burning 25 grains of sulphur in sufficient oxygen ? 3. Which of the following gases should be collected by upward and which by downward displacement: Chlorine, carbon dioxide, hydrogen, sulphur dioxide, ammonia ? 4. A quantity of alcohol, contained in an evaporating dish, was ignited and the burning liquid poured through wire gauze held over a beaker. The flame was by this process confined to the upper surface of the wire gauze, and the greater part of the alcohol collected unignited in the beaker. State the principle upon which the success of this experiment depends. 6. Assign reasons for assuming that the atmosphere is ni)t a chemical compound but a mechanical mixture of oxygen and nitrogen. 6. Describe the physical changes which sulphur undergoes in being heated to 440''O. 7. Write out the equation representing the reaction taking place in the preparation of nitrogen dioxide, and represent by diagram the necessary apparatus for its elimination and collection. 8. A piece of paper satun^d with spirits of turpentina when plunged into a jar containing dry chlorine ignites. Explain. IT 96 EXAMINATION QUESTIONS. il 9. (i.) Write out the equation representing the reaction in preparing the carbon dioxide from calcium carbon- ate and hydrochloric acid. (ii.) How much, by weight, of calcium carbc laUd is required to furnish 12 litres of carbon dioxide, measured at 0°C and yeO*""" P. ? JULY, 1883. 1.- State the law of multiple proportions, and explain your statement by examples. 2. Give the atomic weights (H = 1,) of oxygen, nitrogen, carbon, chlorine, sulphur and phosphorus ; and calcnlate the molecular weight of ammonia, light carburetted hydrogen , sulphuretted hydrogen, nitrous oxide, carbon dioxide, phos - phorus pentoxide, nitric acid and sulphuric acid. 3. Describe a process of preparation and the chief properties of hydrogen. 4. What are the chief properties of oxygen? Give the equations for four processes for the preparation of oxygen, and describe one of these processes. 5. Describe the preparation and properties of carbon dioxide. What are the chief properties of a solution of carbon dioxide in water ? 6. Describe the product of combustion of sulphur in air. In what respect does its bleaching power differ from that of chlorine ? 7. Express by syinbols the reactions which occur when sul- phuric acid is heated together with (a) common jsalt, (6) sal ammoniac, (c) nitre, {d) copper. JULY, 1883. FIRST GLASS TEACHERS — ORADK 0. 1. Explain the full meaning of the following^ merely m ohemioal symbols : — O, OH,, 3 Nag, 00^. reaction in ium carbon- arbc laiie is >n dioxide. cplain your t, nitrogen, 1 calculate i hydrogen , >xide, phos- »f properties ? Give the of oxygen, bon dioxide, rbon dioxide Iphur in air. from that of ar when sul- jsalt, (6) sal , merely m f 2. Th can you Applj composi Oanyi tion to t 3. Th bon, hy carbon, the spe< mulaof 4. De substanc cal chanj oxide, (c (/) "qi 5. Dei (a) C< (6) W (c)Tl (d) A (e) P' (OA 6. W by chlo Dry < 7. Ni give, ac of natt EXAMINATION QUESTIONS. 97 '2. The chemical const.itntion of a gas being known, how can you calculate its specific weight ? - Apply yonr method to find the sp. wt. of the gases whose compositions are — CO,, NHg, C4H10O. Can you mention any gases which form an appareut excep- tion to the general rule ? 3. The ultimate analysis of a substance composed of car- bon, hydrogen, and oxygen, gives, in one hundred parts — carbon, 40 ; hydrogen, 6.6 ; oxygen, 53.4, by weight, and the specific weight of its vapor is 30. Determine the for- mula of the substance. 4. Describe the usual methods of obtaining the following substances, and in all cases illustrate by symbols any chemi- cal changes taking place : — (a) Hydrogen, (6) nitrogen mon- oxide, (c) chlorine, (d) sulphur dioxide, («) sodic carbonatCt (/) "quick" lime, {g) magnesic sulphate, {h) ferric chloride. 5. Describe and explain any phenomena observable, when — (a) Copper is put into strong nitric acid ; (b) Water is mixed with strong commercial sulphuric acid ; (c) The breath is passed for some time through lime*water, and then carbon dioxide is passed through it in excess. {d) A few drops of sulphuric acid is added to a solution of sodic thiosulphatc. (e) Ferrous sulphate is strongly heated in the air. (/*) A drop of a solution of potassic permanganate is added to water containing organic matter. 6. What is the chemical difference in the bleaching effected by chlorine and that by sulphur dioxide ? Dry chlorine will not bleach. Why ? 7. Name the essential constituents of the atmosphere, and give, as far as you can, their particular uses in the economy of nature. 98 EXAMINATION QUESTIONS. QUEEN'S UNIYERSITY. Examiner : ProfeMor McGmoan. JUNIOR CHEMISTRY. FIRST PAPER. 1. Define the gramme, the metre, and the litre, and show their connection. Show how the Fahrenheit and Centigrade thermometric scales are related to each other. 2. Define the following terms, giving illustrative examples : (a) Acid, base, salt, anhydride, hydroxide ; (6) atomicity^ basity of acids, allotropic, isomorphous,. reducing, oxidizing. 3. State clearly what is meant by the terms combustion, explosion, specific gravity, vapour density. 4. (a) Give two methods, in each case, for the preparation of oxygen and nitrogen, and one, in each case, for the prepa- ration of nitric oxide and nitric acid, shewing the chemical changes by formulsB. (6) Give the chief properties of the ! wo last named com- pounds including three different modes of action of nitric acid, explaining these by formulae. 5. (a) Give in writing and by chemical formulee the theory of the manufacture of sulphuric acid, and also a short sketch of the process as carried out ou the large scale. (h) Shew, by examples given, the analogy of the com- pounds of sulphur and oxygen to each other. 6. Give, in writing and by formulae, the theory of Leblano's process for the manufacture of soda ash ; also of the ammonia- soda process. - 7. The coefficient of expansion for gases is 0.003665 for l^G., (or a gas expands from 0° to 1°0 by ^\s of its volume). What will be the change in volume of 150 O.G. of gas if the temperature be raised from 20° to 75° F. and the pressure from 730 to 770 mm. of mercury ? and show nuometric examples : atomicity^ oxidizing. tmbustion, •reparation the prepa- i chemical tmed com- 1 of nitric the theory iort sketch the com* £ Leblanc's i ammouia- ,003665 for 8 volume), f gas if the le pressure 1. Gil bleachin ingpow( 2. Wl ''perma Give process. What 3. W] the sph< 4. M( composi Give < iron f roi blast f u 6. Sh each ot 6. C( maQgai oxides chtoget 7. \^ hydroc potassi writinj 8. G the pi these I for sac EXAMINATION QUESTIONS. 99 SECOND PAPER. 1. Give in writing and by formulae the theory c^ the bleaching action of chlorine, chlorine monoxide, and bleach- ing powder. 2. What is the difference between a " temporarily" and a * * permanently" hard water ? Give the theory of the softening ot waters by Clark's process. What is meant by the " weathering" of siliceous rocks ? 3. What is meant by saying that water boils ? What by the spheroidal state of water ? 4. Mention four of the chief ores of iron, giving their composition. Give descriptions of the old and new methods of obtaining iron from its or^s, and th^ generally received theory of the blast furnace. 5. Show how cast iron, steel, and wrought iron differ from each other. Give the cementation and Bessemer processes manufacture of steel — practice and theory. 6. Compare the ferrous and ferric with the manganons and maQganic salts. Name and give the formulae of the varioufi oxides of manganese, and show how their nature gradually changes with increase of oxygen. 7. What is the action of sulphuretted hydrogen gas on hydrochloric acid solutions of cupric sulphate, arsenious acid, potassic chromate, ferric chloride ? Give the answer both in writing and formulae. 8. Give the theory, and a short sketch of the practice, of the preparation of ethyl alcohol and of ether. State how these may be regarded as being constituted, and give reasons for such statement. i;3 100 KXAMINATION QUESTIONS. -i\ PRACTICAL CHEMISTRY. (Written Examination). 1. The metallic oxides are divided into certain well charac* terized groups. Give the special group tests which determine this division, and name the oxides of each group and give their formulae. 2. Mention two characteristic reactions of each of the following bases — in solution as chlorides : Potassium Oxide (KaO). Calcium Oxide (CaO). Terric Oxide (PeaOg). Oupric Oxide (CuO). 3. How would you distinguish between : ' (a) Zinc and magnesium sulphates ? (6) Lead and mercuric nitrates ? 4. Give as many as you can of the tests for arsenic, in* eluding Marsh's test. 5. Give two characteristic tests for each of the following acids : — Sulphuric ; hydrochloric ; nitric ; oxalic ; hydrosul- phuric (sulphuretted hydrogen) ; hydrocyanic. ft 6. You are given a (soluble) mixture containing salts of copper, iron (ferric) and ammonium : How would you separ- ate these three bases from one another ? 7. Give six characteristic blowpipe or dry reactions for different oxides (supposing you have in each case an easily decomposable salt of the metal). Two of these may be flame colours. ill charac- ietermine and give h of the !aO). O). *8enic, in< following hydroBul- ; salts of rou separ- ctions for an easily Y be flame i w QUI 1. ExpL isomeric, n 2. Expli acid, pota potassic c yr^ter, niti 3. Whal of caustic pyanogen ] 4. How (b) potassi id) nitrog< 5. Wha acts on (a {e) potassi 6. Hoiw tura prod 7. Shoi sulphuric (6) ohlori bonate. 8. Hov position 9. De» lead. H presenoe EXAMINATION QUESTIONS. 101 QUEEN'S UNIVERSITY— SESSION 1883-84. CHEMISTRY. Mkeaminer: Dr. Goodwin. [N. B.— Equations to be given where possible.] 1. Explain the terms compound radiealf effloresencCt baricUy, isomeric, metameric, polymeric. 2. Explain, using formulse, the relations between sulphuric acid, potassic sulphate and potassic disulphate ; between potassic chromate and potassic bichromate, and between w?^ter, nitric acid and orthophosphoric acid. .3. What substances are formed when cold dilute solution of caustic potash is acted on by [a) nitrogen tetroxide, (b) cyanogen gas^ (c) chlorine, (d) bromine, and (e) iodine ? 4k. How would you prepare (a) potassic hydric carbonate {b) potassic bichromate (dichromate), (c) nitrogen monoxide, id) nitrogen tetroxide, and («) red lead ? 5. What substances are formed when strong sulphuric acid acts on (a) sulphur, (6) sugar, (c) mercury, (d) saltpetre, and {e) potassic bichromate ? 6. How do you account for the great decrease of tempera- ture produced by mixing snow and common salt ? 7. Show by equations what substances are formed when sulphuric dioxide acts on solutions of (a) potassic bichromate, (6) chlorine, (c) caustic soda, {d) ammonia, (e) sodic car- bonate. 8. How is bleaching powder prepared ? What is its com- position ? 0. Describe Pattinson's process for separating silver and lead. How is the action of water on lead affected by the presence of ammonia nitrate and calcic chloride ? I 102 EXAMINATION QUESTIONS. I \ 10. How can oxygen be obtained from (a) air, (b) sulphuric acid, (c) mercuric oxide, {d) potassic chlorate, and (e) manga-- nese dioxide ? 11. How is caustic soda manufactured ? What substances are formed when it is heated with sodic acetate ? 12. Give a short account of the metallurgy of zinc, naming its chief ores. 13. From ferric chloride how would you prepare (a) ferric - nitrate, (b) prussian blue, and (c) ferrous chloride ? 14. How many grammes of pure manganese dioxide are required to prepare 10 litres of chlorine gas measured at 17°0 and 750 mm. pressure ? {Mn = 55, O = 16). 15. Explain by equations the alternate action of chlorine and caustic potash on ethylene (defiant gas). 16. How can urea be prepared artificially ? What sub- stances can be formed when it is boiled with solution of caustic soda ? 17. Explain the structure of a candle flame. Explain what takes place when too much air is admitted into the tube of a Bunsen burner. 18. How is the term saponification applied in Chemistry ? What are generally the products of saponification ? 19. What substances can be formed by the action of sulphuric acid on common alcohol? Explain the several actions. 20. Describe completely the action of heat on sulphur. The specific gravity of sulphur vapour near its boiling point is 96, hydrogen = 1 ; at 1040°C, it is 32. What conclusions regarding the molecule of sulphur do you draw from these facta? alphuric manga> >stauoe8 naming a) ferric - xide are at irc chlorine hat 8ub> lution of ain what l;ube of a smistry ? ction of several sulphur, ng point ^elusions m. these JU Valitbb. ' 4 ] 4 4 4 ( 3 by foi 3 . 3 cl< 5 lil be 6 y< 9 it 6 ti 8 . P 6 t V 6 c 5 3x2= 6 ( 10 . < 10 • 1 EXAMINATION QUESTIONS. loa Valubs. 4 4 4 4 3 3 . 3 5 6 9 6 8 6 6 3x2: 6 10 10 JULY EXAMINATIONS, 1884. INTEBMBDIATB AND THTRD GLASS. CHEMISTRY. Examiner: N. F. Dvpuis^ M.A. 1. What is (a) an element ? (&) A molecule ? (c) A dyad? 2. Having water only, what metal would you take by which to obtain hydrogen ? Give the action by formula. Why can you not keep hydrogen pure in a bottle- closed by a common cork ? Are any other gases- like it* in this respect? Mention any law which bears upon this point ? 3. From liquor ammonise of the shops, how can- you^et ammonia gas ? Calculate the specific weight of this gas, and give its prominent properties. Mention any accurate test for the presence of this gas in waiier. 4. If a piece of phoshorus be placed on the wick of a spirit lamp, and the lamp be lighted the phos- phorus will not bum. Explain why. 6. Give the name and composition of the gaa which "burns blue" at the top of the coals in a. common coal stove. How does it get there ? Give any artificial way of obtaining it. 6. Give the names and formulae of any three common sulphur compounds, and shew how any one of them is obtained. 7. If one grain of carbon be completely burned with oxygen, what average volume of carbon diox- ide is produced ? Taloes. 6 6 5 .104 ' EXAMINATION QUESTIONS. SXOOND GLASS TBA0H1CRS — JULY, 1884. Examiner : N. F. Dupuia, M.A. 1. Explain briefly what is meant by atomicity or valence, and give illustrations. ^ ^rite a list of monatomic elements. 2. Mention any differences between an acid and a base. When these are brought together what sub- stances are produced ? Illustrate by an example. 3. Name the substances having the following chemical formulae, and give a short description of any one of them : NaO, HNO3, NH^NOa, HCIO, HaSO*. 4. In the burning of a candle, name the principal products, and describe any experiments which would establish your answer. -6 6. How is chlorine obtained ? To what extent 4 is it soluble in water ? What becomes of chlorine -5 water by exposure to light ? 6 6. Illustrate, symbolically, the action which takes place when sulphur dioxide and hydric sul- phide are brought together. 5 Where does this occur in nature ? 8 7. What is the source, and what are the pro- perties of phosphorus ? •6 Distinguish clearly between yellow and red phosphorus ? ■ 4 When phosphorus burns what is produced ? .6 If the product of the combustion is put. in water what is formed ? ^x2« 10 7 10 omicity (I bcid and at sub- xample. >llowing ption of trincipal I which ; extent chlorine I which Iric sul- the pro- md red jd? put. in Exa 1. State i caloxilate the - Under the its specific v 2. Theore ing substitui (a) Repla (6) Replac (e) Makinj 3. If a n carbon diox will be the < Describe animal orga 4. A piec and starch, Explain tb would cans 5. Expla the black s Which \n by weight 6. Wha What is 7. Thre upon mart lead aceta Find the ployed. ( 8. Give formula f < Alum a EXAMINATION QUESTIONS. 105- ^ 11R8T CLASS, OBADX 0— JULY, 1884. Examiner: Professor K. F. Dupuis, M.A. 1. State Av(^;adro'8 law, and explain how it enables ns to- caloulate the specific weight of a gas. Under the light of this law. prove that air, on account of its specific weight, must be a mixture. 2. Theoretically, what is produced by each of the follow- ing substitutions in the water molecule : — (a) Replacing half the hydrogen by a met by weight of the whole would it give ? (Fe = 56^. 6. What is the average composition of gunpowder ? What is the cause of the explosive force ? 7. Three grams of dilute hydrochloric acid are poured upon marble, and the escaping gas is passed into a solution of lead acetate. The precipitate weighs two grams when dried.. Find the percentage of pure acid (HCl) in the sample em-- ployed. (PB = 207). 8. Give the general constitution of an alum^ and particular formula for two alums in common use. Alum acts as a mmdaid in dyeing. Explain how. 106 KXAMINATION QUESTIONS. TORONTO UNIVERSITY. Chemistry — Second Year— Pass, 1883. Examiner: W. H. Ellis, M.A., M.B. 1. Explain fully why sulphur is called a non-metallic ele* mcnt. 2. What grounds have we for believing that 35 '5 is the atomic weight of chlorine ? 3. Wi4te equations shewing the action of — (a) Potassium on water ; (6) Red hot charcoal on carbon dioxide ; (c) Sulphuretted hydrogen on lead nitrate ; {d) Sulphuretted hydrogen on arsenious chloride. 4. What volume of CO,, measured at 15°C, and 749 mm. Barometer, will be necessary to convert 1 kilo, of carbonate of sodium (Na.jCO„ 10 H,0) into bicarbonate (NaHGOa) ? What weight of chalk must be decomposed to yield this quantity ? Honors, i883. 1. Describe the preparation and properties of Ozone, and give reasons for supposinji^ that ozone may be represented by the formula Og. 2. Give an account of the chemistry of Bromine ? A compound of bromine, oxygen, and silver, is found to contain 45'7 % of silver and 33*9 % of bromine. What is the simplest formula of the corresponding acid ? 3. Describe an experiment to show that when sulphur burns in oxygen the volume of sulphurous oxide formed is exactly equal to the volume of the oxygen consumed. What conclusions do you draw from this fact as to the composition of sulphurous oxide ? 4. Give some account of the chemistry of Zinc. What metal would you class with Zinc ? Why ? 1 ic ele* is the 49 mm. rbonate IO3)? 3ld this ine, and ated by ound to at is the sulphur )Tmed is . What iposition What Acetylene .... Atomic Theory Atom Atomicity .... Atomicity, Tab] Acids ......... Avogadro's Lav Atmosphere .. Ammonia .... Ammonium hyc Binary compou: Bases Bleaching powc Ohemical analy Chemical comp Ohemisu Chemical comt Chemical coml Carbon Carbon raonoz Carbon diozidt Coal gas .... Combustion Chlorine .... Chlorine and o Chloric acid Carbon diaulp Cyanogen ... Density .. Blementi . Bquation, Che Bthene, or Etl Bzamination < Bmpirloal fon INDEX. .J ••;■ PAGE. Acetylene 48 AtumicTheory 5 Atom 9 Atomicity 14 Atomicity, Table of 15 Acids 25 Avogadro's Law 80 Atmosphere 89 Ammonia 82 Ammonium hydrate 83 Binary compounds 24 Bases 26 Bleaching powder 59 Ohemical analysis 77 Chemical compounds 7 Ohemism 10 Chemical combination 18 Chemical combination. Laws of . . 18 Carbon 40 Carbon monoxide 42 Carbon dioxide 48 Coal gas 51 Combustion 61 Chlorine .' 64 Chlorine and oxygen 69 Chloric acid 60 Carbon diaolphide 66 Cyanogen 50 Density 17 Elements 6 Bquation, Chemical 12 Bthene, or Ethylene 48 Bxaminatton Questions 86 BmpirioAl formula 78 PAGE. Formula n Flame structure 52 Oram, weight 17 Halogens 54 Hydrogen ig Hydrates or Hydroxides 26 Hydrochloric acid 56 Inorganic chemistry 5 Impunties of water 28 Liquor ammoniee Litre 16 Metals 6 Mechanical mixture 7 Molecule 9 Metre '. 16 Metric system 16. Marsh gas 46 Non-metals . -. 6 ^.Notation, Chemical 10 Nomenclature 24 Nitrogen 30 Nitrousoxide 34 Nitric oxide 35 Nitrogen trioxide 85 Nitric acid 86 NormalSalt 68 Organic ohemi&try 6 Oxygen 21 Ozone 22 Oxygen and nitrogen 84 Oleilantgas 48 Physical states of matter 8 Potassic chlorate 00 /. ^ . ■/ri 108 INDEX. PAOB. Phosphoros 67 Phosphorus triozfde 69 Phosphorus pentoxide 70 Phosphoric acid, " glacial " 70 Phosphoretted hydrogen 71 Bad'ldes 16 Symbol 10 Specific weight 17 Salts. 26 PAOB. Sulphur 60 Sulphur dioxide 61 Sulphuric acid 62 Sulphuretted hydrogen . . 64 University Exam. Questions 86 Volume 10 Valency 14 Water 28 OOPP, OLARK * CO., ORKKftAL PBINIBRS, OOLBORITI BTBBIT, TOBOKTO.