/ EXCHANGE I. The Detection of Mannite in Alkaline Solutions of Copper Sulphate Combustion of Mannite by Alkaline Solutions of Potassium Permanganate in the Presence of Copper Sulphate |L A Determination of the Volumes of Weight Normal Solutions of Cane Sugar at 15, 20, 25, and 30 DISSERTATION SUBMITTED TO THE BOARD OF UNIVERSITY STUDIES OF THE JOHNS HOPKINS UNIVERSITY IN CONFORMITY WITH THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY, BY HENRY OTTO EYSSELL, BALTIMORE, 1912. GEO. W. KING PRINTING Co., BALTIMORE, Mo. . The Detection of Mannite in Alkaline Solutions of Copper Sulphate Combustion of Mannite by Alkaline Solutions of Potassium Permanganate in the Presence of Copper Sulphate II. A Determination of the Volumes of Weight Normal Solutions of Cane Sugar at 15, 20, 25, and 30 DISSERTATION SUBMITTED TO THE BOARD OF UNIVERSITY STUDIES OF THI JOHNS HOPKINS UNIVERSITY IN CONFORMITY WITH THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY. r>v HENRY OTTO .] YSSKF.L BALTIMORE. GEO. W. KING PRINTING Co.. BALTIMORE, MD. CONTENTS. Acknowledgment 5 I. Detection of Maimite. Introduction 7 Method 7 Strength of Solutions Used 8 Results . 9 Structure of Compound Formed 15 Conclusion 1(1 Combustion of Ma unite Introduction 17 Results 17 Method 18 Check Experiments 19 II. Volume Determinations. Introduction 20 Apparatus 20 Constant Temperature Bath 22 Calculations 2:; Rotations of Solutions 24 Results 24 Summary and Conclusions 29 Biography .31 253952 ACKNOWLEDGMENT. The author wishes to express his sincere gratitude to Presi- dent Remsen, Professors Morse, Jones, Acree, Lovelace and Whitehead for instruction received in the lecture room and in the laboratory. To Professor Morse, the writer wishes to express especial thanks for his personal direction of these investigations and also to Drs. Frazer and Holland for many valuable sugges- tions. PART 1. Tin- Detection of Mannite in All-aline Solutions of Copper Sulphate. The measurement of the osmotic pressure of solutions, which has been in progress in this laboratory for the last ten or twelve years, for the purpose of determining whether this force obeys the laws of gas pressure or not, has thus far been con- fined mainly to solutions of cane sugar and glucose. As soon as practicable, other substances will be dealt with, and mannite will probably be one of the first. of these. In the work with cane sugar and glucose, changes in the con- centration of their solutions can be detected by means of the polarimeter. This method can not be employed in the case of mannite, which made it desirable to work out another for this substance just as delicate, or even more so, than the one based upon the rotatory power of cane sugar and glucose. When the cells containing the solutions whose osmotic pres- sure is to be measured, are set up, they are immersed in a vessel containing an 0.01th ion X, solution of copper sulphate, while the cells themselves always contain a quantity of an 0.01 ion X. solution of potassium ferrocyanide besides the solutions in question. These quantities are believed to be osmotically equivalent, and they are used in this manner for the purpose of repairing ruptures which may develop in the mem- brane while the cells are giving a measurement. It was found that when a solution of mannite is made alka- line with potassium hydroxide and there is then added to it a small quantity of copper sulphate, <i fine blur color is dcreloped without precipitation of copper hydroxide. If more copper sulphate is added, a /trecipitate of copper hi/dro.ri<]< and if still wore of the copper sulphate is added, the fine 8 color referred to eventually disappears, leaving the mannite un- combined witli the copper, but still in solution. At temperatures between and 60, all solutions are made up with 0.001 N. thymol water to prevent the growth of the mould penicillium glaucum, which it seems, thrives upon the nitrogen of the ferrocyanogen anion of the membranes and de- stroys them. It was possible that the thymol might affect this color reaction, or give a similar one under the same conditions, but such was found not to be the case. When solutions of copper sulphate containing thymol in quantities sufficient to make them 0.001 N. with respect to the latter substance, are treated with a solution of potassium hydroxide and filtered through asbestos the filtrates are clear and colorless. This, then, seemed to be a practicable method for detecting the presence of mannite in solution when other substances which act similarly are known to be absent. Several other poly-acid alcohols (glycerol, erythrite and arabite) were found to con- duct themselves in an analogous manner. The solutions of copper sulphate and of mannite used in the subsequent work, were made up with .001 N. thymol water, while the solution of potassium hydroxide was made up with pure water. The solutions of copper sulphate were 0.1 and 0.01 volume normal, that of potassium hydroxide was approximately 0.5 N., each cubic centimeter containing .02805 grams. The solution of mannite contained one milligram of the alcohol per cubic centimeter. Table 1 contains the quantities of mannite and the maximum quantities of copper sulphate, which in 100 cubic centimeters of solution, were found to give a blue colored filtrate after the addition of 5 cubic centimeters of the potassium hydroxide solution. When the copper sulphate exceeded the quantities tabulated by one-tenth of a milligram, the filtrates became practically colorless. TABLE 1. Maximum iian- Manuite. of Topper Sulphate. 1 mg. 37 ing. 2 mg. 88 mg. 3 nig. 107.S mg. 4 mg. 144.0 mg. 5 mg. 180.0 mg. I ing. 1^7.1 mg. 7 nig. 198.3 ing. 8 mg. 236 mg. !> mg. 24.~i.4 mg. 10 nig. 261 mg. Table :! contains The results which were obtained when an attempts was made to duplicate those given in Table 1. The <-anse for whatever discrepancies there are between the results in the two tables was found to be due to the fact that the asbestos filter absorbs and retains some of the coloring: matter. TABLE 2. Ma unite. Maximum Quantities of Copper Sulphate. 1 mg. 36.3 mg. 1 mg. 32.2 mg. 2 mg. 88.0 mg. 2 mg. 97.9 mg. 3 mg. 121.4 mg. 3 mg. 131.4 mg. 4 mg. 144.0 mg. 4 mg. 153.9 mg. 5 mg. 179 9. mg. 5 mg. 177.7 nig. mg. ir.vs mg. Table 3 contains ihe Quantities of copper sulphate and the minimum quantities of mannite which, in 100 cubic centimeters of solution, were found to give a characteristically colored fil- trate after adding ."> cc. <>f the alkali solution. TABLE 3. Minimum Quantity Sulphate. of Mauuite. 10 nig. 0.3 mg. 20 nig. 0.5 mg. 30 mg. O.G mg. 40 mg. 1.1 mir. ~<> in-. 1.4 mg. 10 Table 4 contains the quantities of inannite and the maximum quantities of copper sulphate, which were found to give the col- ored filtrate in 200 cc. of solution after adding 5 cc. of the alkali solution, TABLE 4. Maximum Quantity Mannite. of Copper Sulphate. 1 mg. 34 mg. 2 mg. 64 mg. 3 mg. 92 mg. 4 mg. 122 mg. 5 mg. 154 mg. Table 5 contains the quantities of copper sulphate and the minimum quantities of mannite, which were found to give a colored filtrate in 200 cc. of solution, after making alkaline with 5 cc. of the potassium hydroxide solution . TABLE 5. Minimum Quantity Copper Sulphate. of Mannite. 10 mg. 0.4 mg. 20 mg. 0.7 nig. 30 mg. . 0.9 mg. 40 mg. 1.3 mg. 50 mg. 1.6 mg. Tables f> and 7 contain the results obtained in 100 cc. of solution when the ratio of mannite to copper sulphate was kept constant. The mode of proceedure here and in the following cases was the same as stated above. TABLE 6. Mannite. Copper Sulphate. Filtrate. 1 mg. 25 mg. Colored. 2 mg. 50 mg. Colored. 3 mg. 75 mg. Colored. 4 mg. 100 mg. Colored. 5 mg 125 mg. Colored. 6 mg. 100 mg. Colored. 7 mg. 175 mg. Colored. 8 mg. 200 mg. Colored. 9 mg. 225 mg. Colored. 10 mg. 250 mg. Colorless. 11 The last filtrate was colored, when 10 instead of 5 cc. of alkali were used. Ma unite. 1 ing. 2 mg. 3 mg. 4 mg. 5 mg. 6 mg. 7 mg. 8 mg. 9 mg. 10 mg. TABLE 7. Copper Sulphate. 30 mg. 60 mg. 90 mg. 120 mg. 150 mg. 180 mg. 210 mg. 240 mg. 270 mg. 300 mg. TABLE 8. Copper. Mamiite. Sulphate. Alkali. 1 mg. 60 mg. 140.3 mg. 1 mg. 00 mg. 500.0 mg. 1 mg. 70 mg. ."00.0 mg. 1 mg. SO mg. 500.0 mg. 1 mg. 90 mg. 500.0 nig. Filtrate. Colored. Colored. Colored. Colored. Colored. Colored. Colored. Colorless. Colorless. Colorless. Filtrate. Colorless. Colorless. Colorless. Colorless. Colorless. The filters were washed with 10 cc. of the alkali solution. The washings were all colored. Asbestos filters were used throughout. A new batch of asbes- tos was prepared at this st;ij>e of the work. It was considerably finer than that previously used, and with it colorless filtrates were obtained with ratios which had given colored ones before, ns may be seen from the results given in table 9. TABLE 9. Mannir<>. 1 m::. 1 mp. 1 mg. 1 mir. Copper Sulphate i>.- nig. 1.5 ni.tr. 25 nig. 25 mg. Alkali. 500 mg. 750 mg. 1000 mg. 1250 mg. Filtrate. Colorless. Colorless. Colorless. Colorless. When the filters were washed with 10 cc. of the alkali the washings were 'not colored. They were deeply colored, how- ever, when alkali of Fehling's solution strength was used. Blank experiments gave colored washings with the strong alk- ali, but not with 0.." X. 12 TABLE 10. The solutions were made alkaline with 5 cc. of the potassium hydroxide solution. Mannite. Copper Sulphate Filtrate. 1 mg. 25 mg. Colorless. 2 mg. 50 mg. Colorless. 3 mg. 75 mg. Colored. 4 mg. 100 mg. Colored. 5 nig. 125 mg. Colored. 6 mg. 150 mg. Colored. The filters were allowed to stand for about 15 minutes with 10 cc. of 0.5 N. alkali. The washings were all colored. TABLE 11. Mannite. Copper Sulphate. Filtrate. 1 mg. 50 mg. Colored. 2 mg. 100 mg. Colored. 3 mg. 150 mg. Colorless. 4 mg. 200 mg. Colorless. 5 mg. 250 nig. Colorless. 6 mg. 300 mg. Colorless. The filters were allowed to stand for about 15 minutes with 10 cc. of the 0.5 N. alkali. The washings were all colored. TABLE 12. Mannite. Copper Sulphate. Filtrate. 1 mg. 75 mg. Colorless. 2 mg. 150 mg. Colorless. 3 mg. 225 mg. Colorless. 4 mg. 300 mg. Colorless. 5 mg. 375 mg. Colorless. 6 mg. 450 mg. Colored. 7 mg. 525 mg. Colored. The filters were allowed to stand with 0.5 N. alkali as stated. The washings were all colored, excepting those obtained from the 5 and 7 mg. experiments. Duplicate experiments gave the same results. 13 TABLE 13. The solutions were made alkaline with 5 cc. of the potassium hydroxide solution. Maimite. Copper Sulphate. Filtrate. 1 jng. 100 mg. Colorless. '2 ing. 200 mg. Colorless. 3 mg. 300 mg. Colorless. 4 mg. 400 mg. Colored. 5 mg. 500 mg. Colored. 6 mg. 600 mg. Colored. The filters were treated with 0.5 X. alkali as stated. Where colorless filtrates were obtained the washings were colored, and vice versa. TABLE 14. The solutions were made alkaline with 5 cc. of the potassium hvdroxide solution. Mannite. Copper Sulphate. Filtrate. 1 mg. 10 mg. Colored. 2 mg. 20 mg. Colored. 3 ing. 30 mg. Colored. 4 mg. 40 mg. Colored. 5 mg. 50 mg. Colored. 6 mg. 60 mg. Colored. The filters were treated as in previous cases; the washings were all colored. The results tabulated in tables 6 to 14. inclusive, were ob- tained in 100 cc. of solution. Those given in table 15 were ob- tained in 100 cc. of .01 N. copper sulphate solution. * 14 TABLE 15. Mannite. 1 mg. Copper Sulphate. 123.92 mg. Alkali. 5 cc. 140.3 mg. Filtrate. Colorless. 1 mg. 123.92 mg. 10 cc. 2S0.5 mg. Colorless. 1 mg. 123.92 mg. 15 cc. 420.8 mg. Colorless. 1 mg. 123.92 mg. 20 cc. tiGl.Omg. Colorless. 1 nig. 123.92 mg. 25 cc. 701.3 mg Colorless. 1 mg. 123.92 mg. 30 cc. 841 .5 mg. Colorless. 1 mg. 123.92 mg. 40 cc. 1122.0 mg. Slightly Colored. 1 mg. 3 23.92 mg. 45 cc. 1162.5 mg. Slightly Colored. 1 mg. 123.92 mg. 50 cc. 1402.5 mg. Slightly Colored. 2 mg. 123.92 mg. 5 cc. 140.3 mg. Colorless. 2 mg. ] 23.92 mg. 30 cc. 841.5 ing. Colored. 2 mg. 123.92 mg. 50 cc. 1420.5 mg. Colored. 3 mg. ] 23.92 mg. 30 cc. 841.5 mg. Colored. r > mg. 123.92 mg. 30 cc. 841.5 mg. Deep Color. None. 1 23.92 mg. 30 cc. 841.5 mg. Colorless. None. 1 23.92 mg. 50 cc. 1 420.5 mg. Colorless. 15 The color of the filtered solutions is probably due to 1he for- mation of one of the following compounds : (1) CH*OH CHOH CHOH+GCu(OH) 2 CHOH CHOH CHzOH i i> t CHsOH CHOH 2CHOH+CU (OH) 2 CHOH CHOH CHzOH i :; > CH 2 OH CHOH CHOH+3Cu(OH) 2 CHOH rilOH CH 2 OII CHtOCaOH CHOCuOH CHOCuOII+GHaO CHOCuOH CHOCuOH CHsOCuOH CeHs(OH).-,OCuO(OH)5CoHs+2 H= O. CHip] CHO C 1 Cll HO ] }. CHO J CHO ] j^ CHsO I Working with molecular ratios in 100 cc. of solution, it was found that, at proportions lower than 1 of mannite to 3 of cop- per sulphate, no precipitate was formed, and the color of the solutions increased in intensity upon the addition of 5 cc. of 0.5 X. potassium hydroxide solution. The color of the solution in which mannite and copper sulphate were present in the pro- portion of 1 to 3.5, was no deeper than that of the 1 to 3 solu- tion, and a slight precipitate could be detected in it. These facts would seem to indicate that the color in the case of mannite is due to the formation of compound Xo. 3. 16 Some experiments were made to determine whether nickel salts as well as those of copper could be employed for the de tection of mannite, but with negative results. Conclusions. (1) The colored compound, whatever it may be, which is formed when a little copper sulphate is added to an alkaline solution of mannite, is decomposed by an excess (which is prob- ably a definite one) of copper sulphate for every quantity of maimite. The alcohol is left in solution, but uncombined with copper. (2) Although the colored compound is absorbed, more or less, by the asbestos of the filters, it can be removed from them by washing with alkali. In nearly every case where colorless filtrates were obtained while working with proportions, which had in previous experiments given colored ones, the alkaline washings from the filters were colored. (3) Alkali of the strength used in Fehling's solution can not be employed for, the washing of filters, because it dissolves copper hydroxide, giving a blue solution, while hot water has no effect whatever when used for washing purposes. Although mannite cannot be determined quantitatively by the method described, it will serve very well for the detection of mannite in the liquid exterior to the osmotic cell when leak- age through the membrane is suspected. By means of it two milligrammes can easily be detected in the presence of 123.92 milligrammes of copper sulphate in 100 cc. of liquid. Since the osmotic pressure of a 0.5 N. solution of mannite is about 12.5 atmospheres, a change of two milligrammes in its concentration would make a difference of .00028 of an atmos- phere in the osmotic pressure developed. 17 of Mannitc by Alkaline Solutions of Potassium Permanganate in the Presence of Copper Sulphate. The next question to come under consideration in this con- nection, was that of finding some method for the quantitative determination of mannite, and its oxidation by means of potas- sium permanganate seemed an appropriate one. Theoretically, thirteen atoms of oxygen are necessary for the complete combustion of every molecule of pure mannite. This was verified, experimentally, as may be seen from the results given in the following tables : \. TABLE 1. 2 - e i I 6 d Z C SI si II -1 s ~. j X 5 S3 -y .' <0 1 ing. r. < ( . o::.27 ing. 123.92 mg. 19 hours at 50 4.3 mg. 12.38 1 mg. occ. '.:: 27 mg. li':;. ( .tL' mg. 19 hours at 50 4.4 mg. 12.67 1 mg. r, <-. 03.27 mg. 123.92 mg. 19 hours at 50 4> mg. 13.82 1 mg. - cc. 03.27 mg. 123.92 nig. 19 hours at 50 4.r, mg. 12.96 1 in jr. .- CC. o:;.2~ ing. 123.92 mg. 19 hours at 50 4.4 mg. 12.67 Nont' .- ( ( 93.27 mg. 123.92 mg. 19 hours at 50 None None i* mg. r> cc. 93.27 mg. 123.92 mg. 19 hours .-it 50 9.2 mg. 13.24 2 nig. r. cc. o:;.2~ mg. 11':;. '.12 mg. 19 hours at 50 9.1 nig. 13.10 2mg. 5cc. !>::.2-mg. 123.92 mg. 19 hours at 50 9.0 mg. 12.96 2 mg:. 5 cc. 93.27 mg. 123.92 mg. 19 hours at 50 8.8 mg. 12.67 2mg. 5 cc. 93.27 mg. 123.92 mg. 19 hours at 50 o.l mg. 13.10 None 5cc. 93.27 m-. 123.92 mg. 19 hours at 50 None None 3 mg. 5cc. 93.27 mg. 123.92 mg. 19 hours MI .-,< 13.31 mg. 12.78 3mg. 5cc. 93.27 mir. 123.92 mg. 19 hours at 50 13.18 mg. 12.64 3mg. 5cc. '.::. 27 mi:. 123.92 mg. 19 hours at 50 13.18 mg. 12.64 3 mg. 5 cc. 93^7 mg. 123.92 mg. 19 hours at 50 13.U2 mg. 13.07 " in jr. 93.27 mg. 123.92 nig. 10 hours at 50 13.18 mg. 12.64 None r. cc. 93.27 mg. 123.M2 nig. 10 hours at .-(. None None 4 in-. r, cc. 93.27 mg. 12.-l.02 mg. 19 hours at 50 1 7.s.", mg. 12.84 4 mg. 5cc. 93.27 mg. 123.92 mg. 19 hours ar 50 18.16 mg. 13.07 4 mg. occ. 93.27 mg. 123.92 mg. 19 hours at 50 17.78 mg. 12.M 4 mg. 5cc. 93.27 mg. 123.92 nig. 19 hours at 50 17.72 mg. 12.67 4 me. 93.27 mg. 123.92 mg. 19 hours ar 50 20.09 mg. 14.47 XoiU' occ. 93.27 mg. 123.92 ing. 19 hours at 50 None None ~> mg. 93.27 mir. 123.92 mg. 19 hours ar 50 22.7omg. 13.10 ~ i HIT. .- < -i 93.27 me. 12:;.! 12 mg. 19 hours ar 50 22.51 nig. 12.96 " mg. ~ , ., . '.'::. 27 mg. 123.H2 mg. 19 hours ar 50 22.rr, mg. 13.10 "> mg. r, <<-. '.::. 27 mp. 123.92 mg. 19 hours at 50 22.76 mg. 13.10 -" mg. ."i i < '.:;.L>7 mg. 12:;.92 mg. 19 hours ai 50 22.70 mg. 13.10 N'olH" ~ , .,-. 93.27 mg. 12:1.02 mg. 10 hours ar 50 None None 18 TABLE 2. c5 "3 s g 4 O d o 3 il 4 If I| ^ M t4 y r*iH **<o 10 mg. occ. 1 87.05 mg. 123.92 mg. 19 hours at 50 45.70 mg. 13.15 10 mg. Sec. 187.05 mg. 123.92 mg. 19 hours nt 50 45.45 mg. 13.09 10 mg. 5 cc. 1 87.05 mg. 123.92 mg. 19 hours at 50 45.20 mg. 13.02 10 mg. 5 cc. 1 87.05 mg. 123.92 nig. 19 hours at 50 45.33 mg. 13.05 10 mg. 5 cc. 1 87.05 mg. 123.92 mg. 19 hours at 50 45.39 mg. 13.07 None 5cc. 1 87.05 mg. 123.92 mg. 19 hours at 50 None None 20 mg. 5 cc. 187.05 mg. 123.92 mg. 19 hours at 50 90.28 mg. 12.99 20 mg. 5 ce. 1 87.05 mg. 123.92 mg. 19 hours nt 50 90.53 mg. 13.04 20 ing. 5 co. 1 87.05 mg. 128.92 mg. 19 hours at 50 90.07 mg. 12.96 20 mg. 5cc. 187.05 mg. 123.92 mg. 19 hours at 50 90.07 mg. 12.96 20 mg. 5 cc. 187.05 mg. 123.92 mg. 19 hours at 50 90.22 mg. 12.99 None 5 cc. 187.05 mg. 123.92 mg. 19 hours nt: no None None 30 nig. 5cc. 187.05 mg. 123.92 nig. 19 hours at 50 135.1 mg. 12.97 30 mg. 5cc. 1 87.05 mg. 123.92 mg. 19 hours at 50 135.2 nig. 12.99 30 mg. 5cc. 187.05 mg. 123.92 mg. 19 hours at 50 135.1 mg. 12.97 30 mg. 5 cc. 187.05 mg. 123.92 mg. 19 hours at 50 1 35.05 mg. 12.97 80 mg. 5cc. 187.05 mg. 123.92 mg. 19 hours at 50 135.1 mg. 12.97 Non 5cc. 187.05 mg. 123.92 mg. 19 hours at 50 None None 40 mg. 10 cc. 361.01 mg. 123.92 mg. 19 hours at 50 1 80.95 mg. 13.02 40 mg. 10 co. 361.01 mg. 123.92 mg. 19 hours at 50 181.59ms. 13.08 40 mg. lOcc. 361. Olms". 128.92 mg. 19 hours at 50 182.24 mg. 13.11 40 mg. 10 cc. 361.01 mg. 123.92 mg. 19 hours at 50 181.21 mg. 13.05 40 mg. lOcc. 361.01 mg. 123.92 mg. 19 hours at 50 181.46 mg. 13.08 None 10 cc. 301.01ms. 123.92 mg. 19 hours at no None None 50 mg. lOcc. 432 mg. 1 23.92 mg. 19 hours at 50 224.56 mg. 12.93 50 mg. 10 cc. 432 mg. 128.92 mg. 19 hours at 50 224.09 mg. 12.90 50 mg. 10 oc. 432 mg. 123.92 mg. 19 hours nt 50 224.56 mg. 12.93 50 mg. 10 oc. 432 mg. 123.92 mg. 19 hours at 50 223.58 mg. 12.89 50 mg. 10 cc. 432 mg. 123.92 mg. 19 hours nt no 223.96 mg. 12.90 None 10 cc. 432 mg. 128.92 mg. 19 hours nt no None None The solutions used were made up with water containing no thymol. It was found that the combustion is not complete until the reacting substances have been allowed to stand for a period of 19 hours at 50. A quantity of potassium tetroxalate equiva- lent to the permanganate used was then added, and the excess of tetroxalate titrated back with the standard permanganate solution ; the difference between the two quantities of perman- ganate added being the amount of permanganate reduced dur- ing the'combustion. 10 The mamiite used in this work was analyzed by the electrical method I'm- I he combustion of organic compounds, as devised by I'rnfVssnr Morse, and round to be practically pure. Analysis No. 1 Manuite used. .0909 gms. Per cent, hydrogen found, 7. in;. Per cent, hydrogen theoretical. 7.75. Per cent, carbon theoretical, 39.54. Per cent, carbon found, 39.47. Per cent, purity, 100.2. Atoms of oxygen necessary for complete combustion 13.03. Analysis No. L' Maimite used, .0918 gins. Per cent, hydrogen found, 7.55. Per cent, hydrogen theoretical. 7.75. Per cent, carbon theoretical. oD.54. Per cent, carbon found, 39.27. Percent, purity, 99.01. Atoms of oxygen necessary for complete combustion 12.87 This method can be used for the quantitative determination of mannite in solutions of copper sulphate. The reducing action of thymol upon alkaline solutions of potassium per- manganate is, however, considerably greater than that of man- nite, which will probably necessitate the finding of some other means for coping with penicillium. PAKT 2. A Determination .of tlie Volumes of Weight-Normal Solutions of Cane Sugar at 15, 20, 25 and 30 01 . It is a well known fact that a contraction in volume takes place W:lien sugar is dissolved in water at ordinary tempera- tures, that is, the volume of the solution is not the sum of the volumes of the water and sugar it contains. Determinations of the volumes of sugar solutions at 0, made in this laboratory a few years ago, indicated that when a gram-molecular weight of sugar is dissolved in 1000 grams of water at that tempera- ture, the volume of the solution is about 12 cc. less than the total volume of the water and sugar composing it. This investigation was undertaken for the purpose of throw- ing some light on the amount of contraction occurring at 15 , 20, 25 and 30 in solutions of cane sugar of the concentra- tions thus far used in the measurement of osmotic pressure, for it is hoped that a careful study of their behavior will be of value in explaining in a satisfactory manner the irregularities in the pressures developed by them at lower temperatures. Figure 1 represents the apparatus used in making the meas- urements. It consists of a bulb having a capacity of about 100 cc., and a graduated stem of an inner diameter of about 4 mm. To this, at (c), is fused a calibrated tube about 400 mm. in length, having an interior diameter of about 2 mm. The exact volume of the apparatus up to the mark on the gradu- ated stem, was determined by weighing the bulb with water of a known temperature. In a similar manner the capacity of the stem between the and 100 marks was also determined. The tube was calibrated between the scratches (a) and (b), and 1. This investigation was carried out in collaboration with Mr. F. S 1 . Dengler, in whose dissertation the results obtained for the even concen- trations may be found. s 100 cc FlGURK I 22 ' after it had been fused onto the bulb, the volume of the space be- tween the 100 mark on the stem and the lower scratch (a) of the tube was determined by means of a mercury thread. Eleven such pieces of apparatus were prepared in the manner described, and weighed. Ten of the pieces were then filled with the sugar solutions and the remaining one with air-free water to some point a little above the lower scratch (a) on the calibrated tube. A day or so after the apparatuses had been filled and placed in the constant temperature bath, all of them were found to leak around the stop-cocks to a greater or less extent. They were taken down, and after the stop-cocks had been carefully reground with very fine emory until they were tight, the appa- ratuses were filled again as before. The first measurements were made at 15, and in order to avoid the sticking of the liquid to the walls of the tubes, the solutions and water were cooled below this temperature before filling the dilatometers. To secure reliable determinations of this nature, it is of the utmost importance that the apparatus be kept at a uniform temperature during the experiments, and that any slight changes in temperature which may occur shall be very gradual. In order to secure this uniformity of temperature, a constant temperature bath, originally devised by Morse and Frazer and, described as at present employed in volume 44 of the American Chemical Journal, was used in these experiments. A slight change was necessary in the construction of the bath. The galvanized iron cans used to hold the cells during the measurement of osmotic pressure were replaced by a copper trough large enough to contain all of the apparatuses at the same time. In a bath of this kind temperature fluctuations hardly exceed .01 of a degree. After allowing the dilatometers to stand in the bath at the temperature in question for a period of twenty-four hours or more, the volumes of the solutions contained in them were read by means of a cathetometer. Readings were then taken from day to day until the last three or four consecutive readings re- mained constant. When the necessary readings had been made over the desired range of temperature, the apparatuses and the solutions con- tained in them were weighed. From the weights of the solu- tions in the dilatometers and the measured volumes at the dif- ferent temperatures, the volumes of weight-normal solutions at these temperatures were calculated by simple proportion in this way: Weight of solution : weight of the weight-normal solution : : volume found : volume required. In making these calculations, a correction had to be intro- duced for the solution contained in the hole of the stop-cock. Its volume was determined by means of mercury, and was then added to the measured volume of the solution. The sum of the two volumes is the actual volume of the weight of solution con- tained in the apparatus for the given temperature. Having thus obtained the volume of the weighed amount of solution, its specific gravity was calculated. Knowing the volume of the hole in the stop-cock and the specific gravity of the solution, it was an easy matter to determine the weight of the solution contained in the opening of the stop-cock. This weight was then deducted from the total weight of the solution and the value thus obtained was the weight of solution whose volume had been measured at the temperature in question. This cor- rected weight was the one used for calculating the actual vol- umes of the weight-normal solutions. For the calculations of the sum of the volumes of water and sugar contained in the various solutions, that is, for the deter- mination of the volumes the solutions should have provided there was no contraction, the values 1.5813, as given by Ger- lach and Kopp, and 1.5800 as given by Rchroeder for the specific gravity of sugar in a vacuum at 15 were used, and the value .0001110 as given by Joule and Playfair for the coefficient of expansion of sugar. * 24 The rotations given by the solutions before and after the ex- periments were as follows: TABLE 1. Weight Normality of solutions. 0.1 0.3 0.5 0.7 0.9 -Rotations- Before. 12.60 36.55 58.80 79.20 98.30 After. 12.60 36.55 08.70 77.50 75.00 Tables 2 and 3 contain the results obtained at 15. In Table 2, 1.5813 was taken as the specific gravity of sugar, and 1.5860 in table 3. TABLE 2 (15' 01. 0.3 0.5 0.7 0.9 1000.857 1000.857 1000.857 1000.857 1000.857 !! 21.462 64.386 107.310 150.234 193.158 ZC o OS 1022.319 1065.243 1108.167 1151.091 1194.015 1022.417 1063.952 1106.576 1147.462 1190.359 Js 1 II 0.172 1.291 1.591 3.629 3.656 TABLE 3 (15). 0.1 0.3 0.5 0.7 0.9 5-2 O OS ;> ss 1000.857 1000.857 1000.857 1000.857 1000.857 o o> Is c^ 21.394 64.182 106.970 149.758 192.546 1022.251 1065.039 1107.827 1150.615 1193.403 tf3 1022.417 1063.952 1106.576 1147.462 1190.359 fcfi sl 0.104 1.087 1.251 3.153 3.044 25 Tables 4 and 5 contain the results obtained at 20. In Table 4. 1.5813 was taken as the specific gravity of sugar and 1.5860 in Table 5. TABLE 4 (20) i c ^ = b ill I*: r - "5 - -- II ?! II 11 ^ - ~ z ^" /. ~ -^ ^ > y VI c ~ --. - 0.1 1001. 7." 1 21.474 1023.225 1023.111 0.114 0.3 1001.751 64.422 1066.173 1065.299 0.874 0.5 1001.751 1< iT.370 1109.121 1107.870 1.251 0.7 1001.751 150.318 1152.069 1148.909 3.160 0.9 1001.751 193.266 1105.017 1191.827 3.190 TABLE 20 1 '. S : :_- _; .s . . "" "/ 5- 71* r 7 ii!-= _ = *: 1^ ^ ie Is ~ ? ~ f - ~= ~ z ^ = =- || E^ 0.1 1001.751 1' 1.406 1023.157 1023.111 0.046 0.3 1001.751 64.218 1065.969 1065.299 0.670 0.5 1001.751 107.030 1108.781 1107.870 0.911 0.7 1001.751 149.842 1151.593 1148.909 2.684 0.9 1001.751 192.654 1194.405 1191.827 2.578 Tables 6 and 7 contain the results obtained at 25. In Table 6, 1.5813 was taken as the specific gravity of sugar and 1.5860 in Table 7. TABLE 6 (25). TtE- r t- 11 '..-'- E^- s| || % Z -^ s -*" ^ -" y VI c r: -< > > 0.1 1002.911 l' 1.486 1024.397 1024.343 0.054 0.3 1002.011 64.468 1067.369 1066.464 0.905 0.5 1002.911 107.430 1110.341 1109.404 0.037 0.7 HX>2.911 150.402 1153.313 1150.565 2.748 0.9 1002.911 193.374 1195.285 110.-J.707 3.578 2G TABLE 7 (25). o > ., .4.1 3 fee 1*~ -' t^ C-3 |i t ^0^ "3 si 3 cd -v- C || 1 ^"55 o > if i*- X X * > 0.1 1002.911 21.418 1024.329 1024.343(7) +0.044(7) 0.3 1002.911 64.254 1067.165 1066.464 0.701 0.5 1002.911 107.090 1110.000 1109.404(7) 0.596(7) 0.7 1002.911 149.926 1152.837 1150.565 2.272 0.9 1002.911 192.762 1195.673 1193.707 1.966(7) Instead of a contraction, an expansion appeared to have taken place in the case of the 0.1 weight-normal solution, which is probably due to some experimental error not yet detected, or possibly to the fact that an incorrect value for the specific gravity of sugar has been taken. The irregularity in con- traction exhibited by the 0.5 weight-normal solution must be attributed to experimental error. In the case of the 0.9 weight normal solution it may have been caused by decomposition of the solution which was indicated bv the loss in rotation. Tables 8 and 9 contain the results obtained at 30. In Table 8, 1.5813 was taken as the specific gravity of sugar and 1.5860 in Table 9. TABLE 8 (30). Sal lei gjj * i| Ssfj S o^ [3 cs 3SP S_ e s~ g^s 2o ^1 ^ i ^ > - -3 0.1 1004.314 21.497 1025.811 1025.777 0.034 0.3 1004.314 64.491 1068.805 1068.038 0.767 0.5 1004.314 107.485 1111.799 1111.106 0.693 0.7 1004.314 150.479 1154.793 1152.405 2.388 0.9 1004.314 193.473 1197.787 1195.631 2.156 TABLE 9 (30). i i Li ij -If It ij SSs 5= 5'S 5! t m if ^ 0.1 1004.314 21.430 1025.744 1025.777 +0.033(7) 0.3 1004.314 64.290 1068.604 1068.038 0.566 0.5 1004.314 107.150 1111.464 1111.106 0.358(?) 0.7 1004.314 150.010 1154.324 1152.405 1.919 0.9 1004.314 192.870 1197.184 1195.631 1.553 (?) The same irregularities appear here as in Table 7. The 0.1 weight-normal solution seemed to have expanded instead of contracted. The 0.5 weight-normal solution showed a con- traction, but it was not as large as might be expected. This is also true for the 0.9 weight-normal solution. The various ir- regularities here may be attributed to the same causes given under Table 7. In Tables 10, 11 and 12 are given the expansion coefficients of the various solutions and of air-free water, as calculated from the experimental data. TABLE 10. m fi I i I zy~ > - . > ' ~ s-3 o.l 100.3734 100.4680 .0947 .000189 ".:\ 100.3952 100.5024 .1071 .000213 O.o 100.5770 lOO.OOr,.; .1176 .000234 0.7 100.3743 100.5008 .1265 .000252 0.9 100.4533 100.5872 .1340 .000267 Air-free \vater. 100.407'; 100.407H .ossn .000175 The mean expansion coefficient of air-free water between 1.1" and 20, as calculated from the values given in Landolt-Born- stein, is .000178. 28 TABLE 11. 3!! ig 0.1 100.4680 100.5890 .1210 .000241 0.3 100.5024 100.6323 .1299 .000259 0.5 100.6956 100.8350 .1394 .000277 0.7 100.5008 100.6457 .1449 .000288 0.9 100.5872 100.7369 .1497 .000298 Air-free water. 100.6132 100.6132 .1156 .000230 The mean expansion coefficient of air-free water between 20 and 25, as calculated from the values given in Landolt-Born- stein, is .000232. TABLE 12. 111 32 > Cj o2 Q Kg 0.1 100.5890 100.7298 .1408 .000280 0.3 100.6323 100.7808 .1485 .000295 0.5 100.8350 100.9896 .1546 .000307 0.7 100.6457 100.8066 .1606 .000320 0.9 100.7369 100.8983 .1614 .000320 Air-free water 100.6132 100.7507 .1375 .000274 The mean expansion coefficient of air-free water between 25 and 30, as calculated from the values given in Landolt-Born- stein, is .000280. In Table 13 are given the expansion coefficients of the various solutions as calculated from the experimental data in terms of the volumes at 15. 29 TABLE 13. isjj 1^ s| if S^-I fl-2 ||= ||.-, 0.1 .000189 .000.241 .000280 0.3 .000213 .000259 .000296 0.5 .000234 .000277 .000307 0.7 .000252 .000288 .000320 .09 .000267 .000298 .000321 The solutions whose rotation changed during the investi- gation all contained a growth of some sort, probably penicil- liuiu. The results given in the tables for the concentrations greater than O.G normal are not reliable, because those were the solutions which contained more or less of the growth men- tioned, and whose rotation had changed, in some cases very considerably. It is possible to correct for inversion by taking the loss in rotation into account, but it would be useless to do so, since it can not be stated with certainty that further decomposition did not take place. In spite of the numerous valueless results obtained, it seems evident from the foregoing results; (1) that, when cane sugar is dissolved in water at any given temperature, the contraction in volume increases with the concentration of the solutions; - i that, for any given concentration, it decreases with rise in temperature. BIOGRAPHY. Henry Otto Eyssell was borin in Kansas City, Mo., February 23, 1885. He received his early education in the public schools of his native city. In September, 1904, he entered the Univer- sar of Missouri, where he received the degree of Batchelor of Arts in June, 1908. In October, 1909, he entered the Johns Hopkins University as a graduate student in Chemistry. UNIVERSITY OP CALIFORNIA LIBRARY THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW OCT 18 1916 30m-l,'15 253952