9 i General and Physical Chemistry. Emission Spectrum of Ammonia. By G. MAGNANINI ( Z e i t . physikal. Chern., 4, 435-440) .-The author has determined the positions of a large number of the lines of the ammonia spectrum. These are compared with the lines of Hasselberg’s second hydrogen spectrum, with which they show a remarkable coincidence. Absorption Spectrum of Nitrosyl Chloride. By G. MAGNANINI (Zeit. physikol. Chem., 4, 427-428).-The absorption spectrum of nitrosyl chloride vapour consists of six absorption bands in the orange and green parts of the spectrum. The wave-lengths corresponding with these bands and their relative intensities are given. By S. KALISCHER (Ann. Phys. Chem. [2], 37, 528).-The author observes that Righi (Abstr., 1889, 555) appears to have misunderstood a remark made by him in a former note (ibid., 3).He had pointed out that selenium cells often give an E.M.F. before exposure to light, and that, therefore, before experimenting on the influence of light on them, they should be tested in the dark to see if they already give any E.M.F. He had no inten- tion of asserting the necessity of actually manufacturing the cells in darkness, and preventing their even being exposed to light before experimenting with them. Electrical Conductivity of Hydrogen Chloride in Different Solvents. By I. KABLUKOFF (Zeit. physikal. CRem., 4, 429434).- The conductivity of solutions of hydrogen chloride in benzene, xylene, hexana, and ether is excessively small, that in ether being greatest and that in benzene the least. The molecular conductivity of the solution in ether is found to decrease with rising dilution. Solutions of hydrogen chloride in methyl, ethyl, isobntyl, and isoamyl alcohols have a somewhat greater conductivity.The methyl alcohol solutio~is have the highest conductivity, being about four times greater than the ethyl and 30 times greater than the isobutyl alcohol solutions. Amy1 alcohol, like ether, gives a decreasing molecular conductivity with rising dilution. Hydrogen chloride was also examined i n aqueous solutions of ethyl alcohol. The presence of ethyl alcohol is found to greatly decrease the conductivity of hydrogen chloride in water, An addition of 6 per cent. of alcohol causing a decrease of 20 per cent. in the conductivity. If a solution of benzene saturated with hydrogen chloride is allowed to remain for two or three days, crystals separate out which melt without decomposition, and can be sublimed a t high temperature.They are probably of the composition CsH6,3HCI. H. C. H, C. Electromotive Force of Selenium. G. W. T. H. C. VOL. LTlII. h98 ABSTRACTS OF OHEMIOAL PAPERS. Electrical Coqductivity of Solid Mercury. Bp L. GRUNMACH (Ann. Phys. Chem. [2], 37, 308--515).-As the result of a further experimental investigation of this subject,, tbe author finds that the apparent resistance of mercury when just melted is 2-5 times its value just before liquefaction begins. The value 1.5 formerly obtained by the author (Abstr., 1889, 201) is, therefore, too small. The value now obtained by him is smaller than that given by Cailletet and Bouty, namely 0.4, and the anthor attributes the difference between his present and former results, and between both of them and that obtained by Cailletet and Bouty, in great part to the change in volume which mercury undergoes in passing from the solid to the liquid state, and the effects of this change of volume on the resistance, depending as they do on the dimensions of the tubes and their regularity of bore.The degree to which the result is affected in this manner cannot be determined until these changes of volume have been measured, and the author states that an investigaticn of this point has been commenced. The results of the investigation described in this paper confirm the conclusion formerly arrived at by the author, that the temperature- coefficient of decrease of resistance for solid mercury decreases from the solidifying point down to -80°, the lowest temperature at which observations were made.The values obtained for this coefficient i n the former and present series of observations respectively are given below :- Range of Tempemture-coefficient. Temperature-coefficient. temperature. First series. Second series. -80" to -70" 0~0010 0-0008 -70 ,, -60 0*0010 0*0011 -60 ,, -50 0.0012 0.0015 -50 ,, -40 0.001 7 0.0023 The results of the present investigation therefore confirm the con- clusion formerly arrived at by the author, that assuming the truth of Clausius's law expressing the relation between the electrical resist- ances of simple metals and their absolute temperatures, then mercury must be considered a8 an exception. G.W. T. Thermoelectric Currents between Amalgamated Zinc and Zinc Sulphate. By K. A. BRANDER (Ann. Phys. Chem. [2], 37, 457-462).-The primary object of the investigation was to determine the relation between the E.M.F. developed and the difference of temperature between the electrodes. The electrodes, of amalgamated zinc, were placed in two vessels communicating by means of a siphon, and filled with a solution of zinc sulphate. One of these vessels was kept at the temperature of the place of observation, while the temperature of the other was gradually raised. The author found that, within the limits of errors of observation, the E.M.F. was proportional to the difference of temperature, until thisOEXERAL AND PHYSICAL CHENISTRT.99 difference exceeded 20.45", after which the E.M.F. appeared to increase rather more rapidly than the temperature difference. A few experi- ments were also made to determine the effect of varying the concen- tration of the zinc sulphate solution, and their results showed that the E.M.F. increased with the concentration. G. W. T. Electrochemistry and Thermochemistry of some Organic Acids. By H. JAHN (Anla. Phys. Cliem. [2], 37,40843). B'ormic Acid.-When a solution of sodium formate in water was acidified with formic acid and subjected to electrolysis, i t yielded hydrogen and carbonic anhydride. The sodium salt must first be resolved into sodium and the group HC02, the former forming sodium hydroxide with the water of solution, whilst the latter must either break up into carbonic anhydride and hydrogen or form formic acid again with the water of solution, according to the equation 2H + CO, + H20 = 2H2C02 + 0, the free oxygen then combining with a portion of the formic acid to form carbonic anhydride and water.Now Bunge has shown that in the electrolysis of formic acid no hydrogen is given off at the anode, which excludes the first explanation, and shows that a simple combus- tion of the acid takes place at the anode. The results were confirmed by determinations of the amount of gas liberated by the passage of a measured quantity of electricity. The author made a series of determinations of the heat of combus- tion of formic acid which agreed very well together, and their mean gave 62.87 cal. as the heat of combustion of a milligram mole- cule of formic acid.Thomsen obtained the value 60.2 cal., and the author observes that this may be considered as a very cloAe agreement, considering that, as Ostwald has shown, the heat of combustion varies considerably with the temperature. Acetic Acid.-A solution of sodium acetate in water was electro- lysed at the temperature 0". A considerable quantity of carbonic anhydride was formed, and after the gds given off had been freed from this, the residue was found to consist of hydrogen and ethane, about 65 per cent. of the former and 35 per cent. of the latter. Very slight traces of iodoform were obtained from the liquid residue in the electrolytic cell, From this i t follows that the action consisted in the setting free of acetic acid at the anode, and its combination with the oxygen simultaneously liberated; but if this took place entirely in the manner usually assumed, 2C2H402 = C2H, + 2C0, + H,O, the volumes of hydrogen and of ethane wodd have been equal.The excess of hydrogen present, combined with the absence of free oxygen, shows that, part of the acetic acid must have been burnt to form carbonic anhydride and water, according to the equation C2H402 + O4 = 2C02 + 2H20. In some quantitative experiments made with stronger currents, the proportion of hydrogen was found to be somewhat smaller. The proportion of hydrogen present in the evolved gases was also found to diminish as the strength of the solution wos increased. These results show that the complete com- bustion of the acetic acid to carbonic anhydride and water is favoured h X100 ABSTRACTS OF CHEMICAL PAPERS.by increasing the strength of the decomposing current, and by dimi- nishing the strength of the solution. Assuming Thornsen's values for the heats of solution required for the calculation, the author determined the heat of combust,ion of the milligram molecule of liquid acetic acid to water and gaseous carbonic anhydride to be 208.81 cal., which is in very fair agreement with the values 210.3 obtained by Fabre and Silbermann, and 210.79 obtained by Stobmann. It follows from the last result that the heat absorbed in the formation of one milligram molecule of liquid acetic acid from amorphous carbon and water vapour is 121.61 cal. Propionic Acid.-The results obtained with acetic acid suggested that propionic acid would probably be resolved into normal butane and carbonic anhydride, and t,he electrolysis of a solution of sodium propionate in water, acidified with propionic acid, showed that this reaction did actually occur, but it was veiled to a considerable extent by the decomposition of part of the acid into ethylene and carbonic anhydride, evidently according to the equation C2H602 + 0 = C,H, + CO, + H20.The author considers that the results of his experi- ments with acetic and propionic acids point to the conclusion that the ethane and butnnc formed during electrolysis are the results of the decomposition of double molecules, which exist in concentrated solu- tions, but are broken up into simple molecules when the solutions are diluted. Oxalic Acid.-The electrolysis of an aqueous solution of potassium oxalate a t the temperature 0" gave a gas consisting only of carbonic anhydride and hydrogen, so that the oxalic acid set free at the anode must have been completely burned to carbonic anhydride and water, according to the equation H2C20, + 0 = 2C0, + H20.The heat of combustion of oxalic acid per milligram molecule was found to be 74.49 oal. G. W. T. Thermochemistry of Methyl Alcohol and Solid Methyl Salts. By F. STOHMANN, C. KLEBER, and H. LANGBEIN ( J . p . Ohm. [ A ] , 40, 342-364) .-The authors give details of the determination of the following thermal values (see table, y . 101). The figures in the sixth column represent the exces,s or deficiency of the heat of combustion of the methyl salt when compared with the sum of the heats of combustion of the acid from which it is formed and methyl alcohol (compare Berthelot, Mhanique Chirnique, 1, 407).The authors then point out the difference bettween the heats of combustion of the various isomerides in this table, and also give a table showing the value of the affinity constant K (Ostwald, Abstr,, 1889, 818) for 24 acids, 20 of which agree with the rule.GENERAL AND PHYSICAL CHEMISTRY. Table of thermochemical results with methyl-compounds. Methyl gallate.. ......... Methyl P-naphthoate ..... Dinrethgl phthalate (liquid) Dimethyl phthalate (solid) Substance. C&H806 .. C12HloO.: . ClQHlo04. C10H1004 . Formula. Dimethyl terephthalate ... Dimethyl oxalate. ........ Dimethyl succinate (solid). ,) ,, (liquid) Dimethyl fumarate ......,, citrate. ........ Methyl alcohol. .......... Trimethyl trimesate ...... Hexamethyl mellitate.. ... Citric acid .............. C10Hl004 . C4H604 .. C&l,Od. . C6H100d.. CGH,04 .. CVHI,O;. . CH,O.. .. C12H&6 . C,e131sO12. C,H,O, .. Molesular weight. 152 166 162 184 186 194 194 194 194 118 146 146 144 252 234 426 192 32 Heat of cumbus- tiou. Cal. 896 -0 €069 '3 1213.6 801 *3 1402 -4 1120 -4 1113 -9 1117 *'7 1112 *2 402 -1 703 *6 708 -5 664 *7 1292 5 983 -5. 1825 -6 474 *6 170.6 Heat of forma- tion." Cal. 132 .O 121 -7 71.4 226 .7 70 -6 164 *6 171 -1 1'73 *3 172 ,8 180 *9 205 -4 200-5 175.3 249 *5 345 - 5 487-4 365 - 4 61 -4 101 - ' 0 . 5 -3.5 -0.7 1-3-4 -3.4 - 1 . ~ 1 -1.7 -0.1 -0.7 -5.6 -3-4 -13.1 + 2 * 9 -13 ' 8 - - - - * C = 94 Cals.; H2 = 69 Cals.A. G. B. Thermochemistry of' Nicotine. By A. COLSON (Covyt. r e d . , 109, 743-745) .--Nicoti?ze.-Heat of dissolution + 6-6 Cals. at about 15" ; heat of neutralisation by hydrochloric acid, 1st equivalent = 8.05 Cals. ; 2nd equivalent = 3.47 Cals. Total heat of neutyalisation by 4 mols. HC1 = 12-06 Cals. With sulphuric acid, 1st equivalent = 9.54 Cals.; total heat of neutralisation by excess of acid = 13.46 Cals. It is evident that the two basic functions of nicotine have very different energies, a fact which is also shown by colour reagents. With litrnius as indicator, nicotine has only one basic function, but with dimethyl-orange it Gas two. The author has also made the following determinations :- Pyridine. Piperidine. Csls. Cals.Heat of dissolution.. ................ 2.25 6-50 Heat of neutralisation, 1 mol. HC1 .... 5.20 13-01 - 7 , Y9 1.5 mol. HC1 . . 5.20. ,Y 9 ) 13.68 1 mol. H2S04 . . - C. H. B. Apparatus for making Vapour-density Determinations under Reduced Pressure. By J. F, EYKMAN (Ber., 22, 275&2758).-- The author describes with the aid of diagrams an apparatus in which vapour-density determinations may be made under reduced pressure, and in an atmosphere of hydrogen or some other indifferent g&s. The apparatus consists of it bulb-tube (A), somewhat similar in102 ABSTRACTS OF CHEMICAL PAPERS. shape to that employed in V. Meyer's method; this is heated by some suitable vapour in the ordinary way. A weighed quantity of the liquid, the vapour-density of which is to be determined, is placed in a small, sealed, pipette-shaped tube, and suspended in a chamber in the upper extremitly of the bulb-tube (A).The latter is connected a t the top with a graduated manometer tube, placed perpendicularly and open below, and also with a 3-way cock, so that it can be exhausted and filled with hydrogen or any other gas. The apparatus having been completely filled with hydrogen, it is exhausted as com- pletely as pos>ible, the open end of the manometer being immersed in mercury ; the bulb-tube is then heated a t a constant temperature, and hydrogen is allowed to enter until the required pressure is obtained. As soon as no more mercury flows out of the manometer tube, the pressure is noted on the scale, and the neck of the bulb containing the substance is broken without opening the apparatus, by an inge- nious device, so that i t drops to the bottom of the bulb-tube (A), and is there converted into vapour.The pressure is thereby increased, and the mercury which flows from the manometer tube is collected in a tared vessel ; the increase of pressure is ascertained either by weigh- ing the mercurg, the diameter of the msiiometer tube having been previously determined, or from the difference in tlhe readings on the manometer scale. The vapour-densi ty is calculated from the increase of pressure produced by the vaporisation of a known weight of the substance in a vessel of known volume under known conditions of temperafure and pressure. Experiments with safrole (b. p. 232"), ethyl cinnamate (b. p. 271"), naphthylamine (b.p. 300°), phenylpropionic acid (b. p. ZOO0), and other sitbstances gave very satisfactory results. The apparatus can be employed also for making determinations by V. Meyer's method in the usual way. I?. S. K. Specific Volumes of some Ethereal Salts of the Oxalic Acid Series. By A. WIENS (Annalen, 253, 289-318 ; compare W. Lossen, Abstr., 1888, 335).-A comparison of the molecular volumes of meta- meric ethereal salts of oxalic, malonic, succinic, and glutaric acids, containing normal alkyl radicles, shows that the larger the quantity of carbon in the acid radicle the smaller the molecular volume a t 0". This is generally the case at the boiling point also, but two exceptions were noticed, the molecular volume of ethyl propyl malonate being smaller than that of ethyl succimte, and that of bntyl malonate smaller than that of propyl butyl succinate ; these exceptions may be due to the uncertainty of the determinations at the boiling point.The difference in molecular volume corresponding with the difference in composition increases in homologous series with the quantity of carbon in the compound. The difference between the molecular volume of ethyl methyl succinate and ethyl butyl succinate, for example, is 71.3 ; that bet,ween ethyl butyl succinate and ethyl heptyl succinate, 76.4. The same has been found to hold good for ethereal salts of monobasic acids, ethers, phenol ethers, and nlkyl iodides. A comparison of the molecular volumes a t 0" shows that an increase by the group C'H, in the empirical formula corresponds with variousOESERAL AND PHYSICAL CHEMISTRY. 103 differences in molecular volume, according to the manner in which this increase takes place.The increase in molecular volume by the conversion of the group CnH2n+l into ( CH2)z*CnHzn+tl (excluding methyl salts) is, on the average, 16.8 for each CH? group, but the difference between the ethyl and methyl salts is, on the average, 18.1. The increase, due t o the conversion of the group CH2 into (CH,)., is, on the average, 16 for each additional CH2 group, but when the group CH, is converted into CHMe (ethyl into isopropyl, for example), the corresponding increase in molecular volume is, on the average, 17.7. The numerous experimental determinations are given in tables. F. S. I(. Absorption of Gases by Mixtures of Alcohol and Water.By 0. LCBARSCH (Ann. Phys. Chem. [2], 37, 524-525).-The author observes that the publicat,ion of Muller's determinations of the absorp- tion of carbonic snhydride by mixtures of alcohol and water (Abstr., 1889, 816) has induced him to publish the results obtained so far in an investigation of the absorption of various gases by mixtures of alcobol and water ; these are given in the accompanying table, showing the percentages by volume of the gases absorbed at 20" and 760 mm. pressure by solutions containing the various percentages of alcohol (by weight) given in the first horizontal line :- Percentage of alcohol.. .. 0-00 9-09 16.67 23.08 2857 33'33 5 0 W 66.67 80~00 Oxygen. .. .. 2-98 2-78 2.63 2.52 2-49 2-67 3-50 4.95 5-66 Hydrogen. ,.1-93 1.43 1.29 1-17 1.04 1.17 2.02 2.55 - Csrbonicoxide 2.41 1.87 1.75 1.68 1-50 1'94 3'20 - - The table shows that the minimum absorption for all three gases occurs at about the same proportion of alcohol to water, and this is the same as that found by Muller for carbonic anhydride, and there- fore it seems probable that other gases will be found to behave in the same way. G. W. T. Simultaneous Solubility of Sodium and Potassium Chlorides. By A. @,CARD (Compt. rend., 109, 740-743).-The sum of the salts dissolved between -20" and +180" is represented by a straight line, yf$" = 27.0 + 0-0962t. Calculating from this coefficient the tem- perature at the limit of solubility, that is, the point at which, by reason of the increase in the proportion of salt and the decrease in the proportion of water, the latter has disappeared, the temperature obtained is 738", which, according to Carnelly, is the melting point of potassium chloride.In presence of potassium chloride, the curve of solubility of sodium cliloride between -20" and + 75" is parallel with the axis of tempera- ture. Beyond 75" it decreases, and at 97" becomes identical with that of potassium chloride, after which it decreases to 120", and then becomes constant (16.7 per cent.). The solubility of potassium chloride alone is represented between104 ABSTRACTS OF CHEMICAL PAPERS. I -10" and + 75" by a right line with a coeficient 0.1470, and bztween 75" and 180" by a second right line, which has a coefficient of 0.0793, and a limiting point at 913", or considerably above the melting point of the salt.In presence of sodium chloride, the curve of solubility of potassium chloride between -20" and + 75" is a right line y = 10.3 + 0.0962i ; from 75" to 120" the solubility increases rapidly, and above 120" it is represented by a righ't line with the same coefficient as between -20" and +75". Its limit,ing point is 913", and hence the curves of solu- bility of potassium chloride alone and in presence of sodium chloride are not parallel, but converge to 913". At the limiting point for the mixed salts, 738", the proportion of the two salts would be 16.7 per cent. of sodium chloride and 83.3 per cent. of potassium chloride. The total quantity of chlorine is prac- tically equal to the sum of the metals. The curve representing the quantity of chlorine in solution is a right line ; that liepresenting the sum of the salts is also a right line ; and hence the sum of the metals is likewise represented by a right line.The curve of the chlorine and the curve of the sum of the metals intersect at 738". C. H. B. Determination of Molecular Weights of Substances from the Boiling Points of their Solutions. By H, W. WILEY (Chem. News, 60,189-190) .-"The appnratus employed consisted of an oval- round bottom flask of about 200 C.C. capacity," with a side tube from the neck connected with a condenser to keep volume of liquid constant. A thermometer graduated to tenths, but capable of being read to 0.02 of a degree was employed, the bulb being enveloped in fine copper foil to prevent interference of bubbles of steam.Sodium chloride was used to determine the fkctor, the number obtained, 8.968, was used for calculating the results in the following table ; the volume of wat)er being in all cases 150 C.C. ; the temperature of boiling water was 99.50" except during the experiments with sodium nitrate, when it was 99.44". K C1. ................. KBr., ................ EI ................... KNO, ................ E,Cr,Oj .............. NaN03 ............... Saccharose ............ Oxslic acid.. .......... 6 *O 6 '0 9 '0 6 '0 18 -0 6 . 0 20 *o 6 .O ~ _ _ _ _ _ _ _ _ _ _ Total rise of temperature. -- 0 '35O 0 *29 0 *33 0 *33 0 *38 0 *42 0.20 0 -20 ~ ~~ Molecular weiglit. Calculated. -- 76 -91 123 -7 163 '1 108 *7 283 -2 85.4 643-2 179 *4! Theoretical. 74.5 119 .o 166 -0 101 -0 295 -0 85.0 342 *O 90 -0 --- It will be noticed that the two organic compounds give double the theoretical molecular weight by this method.The resultsGENERAL AND PHYSICAL CHEMISTRY. 105 obtained with salts containing water of crystallisation do not agree with the molecular weights with or without this water. These results were obt,ained quig independently of those of Beckman. D. A. L. Behaviour of Colloi’d Substances wlith Respect to Raoult’s Law. By E. PATERNO (Zeit. physikal. Chem., 4, 457--461).-The reduction of the freezing point by colloid substances in water is very slight, and therefore leads to very high numbers for the molecular weights of such substances (Brown and Morris, Trans., 1889, 462). This, the author has observed, is the case with gallic and tannic acids ; which behave like collo’ids in aqueous solution and give molecular weights many times greater than those ordinarily accepted for these substances.If, however, solutions in acetic acid are taken, the behaviour is found to be perfectly nornial, and the reduction of the freezing point is that corresponding with the ordinary simple mole- cular weights. Hence substances only behave as colloids towards certain solvents, and the author holds that when a solid dissolves as a colloid, the laws of freezing are not applicable to its solutions. H. C. Can Raoult’s Method distinguish between Atomic and Molecular Union ? By R. ANSCH~~TZ (Annalen, 253, 343-347 ; compare Anschutz and Pulfrich, Abstr., 1888, 1273).-The depres- sion produced by naphthalene picrate in the freezing point of benzene corresponds with that which would be produced by its constituent parts present together in an uncombined state.The author concludes therefore that the combination of the coniponents of naphthalene picrate and analogous substances such as dimethyl diacetjlracemate is not dependent on atomic union in the sense of the valence theory, but on molecular union. If Raoult’s method is capable of deciding between atomic and molecular union, it could be employed for determining the valency of elements. F. S. I(. Kinetic Nature of Osmotic Pressure. By G. BREDIG (Zeit. physikal. Chem., 4, 444-456) .-In replying to certain objections raised by Pupin against the Van’t Hoff theory of osmotic pressure (Abstr., 1888, 7i8), the author develops an equation for the behaviour of a dissolved substance which is similar to that of Van der Wads for the behariour of gases.A special point of interest is, that account is taken of the presence and specific attraction of the solvent. and in this way an explanation of the mechanism of solution is obtained, which, it is claimed, is of wider application than that of Nernst (this vol., p. 3), in which this attraction is neglected. Sphere of Action of Molecular Forces. By B. GALITZINE (Zeit. physiknl. Chem., 4, 417426).-By a process of theoretical reasoning similar to that already employed by Van der Waals, and using data given by Nadeschdin for several of the ethereal salts of the fatty acids in the critical condition, the author arrives at the conclusicsn that the sphere of action of the molecular forces is proportional to H.C.106 ABSTRACTS OF CElEMIOAL PAPERS. the masses of the attracting molecules. attraction is inversely proportional to the square of the distance. He also concludes that the H. C. Fluid Crystals. By 0. LEHMANN (Zed. physilcal. Chem., 4, 462- 472).-Under the name of "fluid crystals," the author describes a cbolesteryl benzoate first prepared by Reinitzer, which, although apparently melting at 145", behaves between 145" and 178" towards polarised light as though still having crystalline structure. In other respects the substance is in a perfectly liquid condition between these temperatures. H. C. New Gas Burners. By M. GROGER (Zeit. any. Qhem., 1889,329- 331).-These are in general form similar to Bunsen burners, but instead of having any means of regulating the entry of air at the bottoni of the mixing tube, the top of the burner is made conical, and there is a screw arrangement by which a solid cone can be raised within, so as partially to close the opening.By this means a flame of any character can be obtained, from a luminous one to one approaching that of a blowpipe, whilst the size of the flame can be greatly reduced without altering its character, and without risk of its flashing down. A burner on the same principle giving a flat flame is also described. M. J. S.9 iGeneral and Physical Chemistry.Emission Spectrum of Ammonia. By G. MAGNANINI ( Z e i t .physikal. Chern., 4, 435-440) .-The author has determined thepositions of a large number of the lines of the ammonia spectrum.These are compared with the lines of Hasselberg’s second hydrogenspectrum, with which they show a remarkable coincidence.Absorption Spectrum of Nitrosyl Chloride.By G. MAGNANINI(Zeit. physikol. Chem., 4, 427-428).-The absorption spectrum ofnitrosyl chloride vapour consists of six absorption bands in the orangeand green parts of the spectrum. The wave-lengths correspondingwith these bands and their relative intensities are given.By S. KALISCHER (Ann.Phys. Chem. [2], 37, 528).-The author observes that Righi (Abstr.,1889, 555) appears to have misunderstood a remark made by him in aformer note (ibid., 3). He had pointed out that selenium cells oftengive an E.M.F. before exposure to light, and that, therefore, beforeexperimenting on the influence of light on them, they should be testedin the dark to see if they already give any E.M.F.He had no inten-tion of asserting the necessity of actually manufacturing the cells indarkness, and preventing their even being exposed to light beforeexperimenting with them.Electrical Conductivity of Hydrogen Chloride in DifferentSolvents. By I. KABLUKOFF (Zeit. physikal. CRem., 4, 429434).-The conductivity of solutions of hydrogen chloride in benzene, xylene,hexana, and ether is excessively small, that in ether being greatestand that in benzene the least. The molecular conductivity of thesolution in ether is found to decrease with rising dilution. Solutionsof hydrogen chloride in methyl, ethyl, isobntyl, and isoamyl alcoholshave a somewhat greater conductivity.The methyl alcohol solutio~ishave the highest conductivity, being about four times greater thanthe ethyl and 30 times greater than the isobutyl alcohol solutions.Amy1 alcohol, like ether, gives a decreasing molecular conductivitywith rising dilution. Hydrogen chloride was also examined i naqueous solutions of ethyl alcohol. The presence of ethyl alcohol isfound to greatly decrease the conductivity of hydrogen chloridein water, An addition of 6 per cent. of alcohol causing a decrease of20 per cent. in the conductivity.If a solution of benzene saturated with hydrogen chloride is allowedto remain for two or three days, crystals separate out which meltwithout decomposition, and can be sublimed a t high temperature.They are probably of the composition CsH6,3HCI.H. C.H, C.Electromotive Force of Selenium.G.W. T.H. C.VOL. LTlII. 98 ABSTRACTS OF OHEMIOAL PAPERS.Electrical Coqductivity of Solid Mercury. Bp L. GRUNMACH(Ann. Phys. Chem. [2], 37, 308--515).-As the result of a furtherexperimental investigation of this subject,, tbe author finds that theapparent resistance of mercury when just melted is 2-5 times itsvalue just before liquefaction begins.The value 1.5 formerly obtained by the author (Abstr., 1889, 201)is, therefore, too small. The value now obtained by him is smallerthan that given by Cailletet and Bouty, namely 0.4, and the anthorattributes the difference between his present and former results, andbetween both of them and that obtained by Cailletet and Bouty, ingreat part to the change in volume which mercury undergoes inpassing from the solid to the liquid state, and the effects of thischange of volume on the resistance, depending as they do on thedimensions of the tubes and their regularity of bore.The degree towhich the result is affected in this manner cannot be determined untilthese changes of volume have been measured, and the author statesthat an investigaticn of this point has been commenced.The results of the investigation described in this paper confirmthe conclusion formerly arrived at by the author, that the temperature-coefficient of decrease of resistance for solid mercury decreases fromthe solidifying point down to -80°, the lowest temperature at whichobservations were made.The values obtained for this coefficient i n the former and presentseries of observations respectively are given below :-Range of Tempemture-coefficient.Temperature-coefficient.temperature. First series. Second series.-80" to -70" 0~0010 0-0008-70 ,, -60 0*0010 0*0011-60 ,, -50 0.0012 0.0015-50 ,, -40 0.001 7 0.0023The results of the present investigation therefore confirm the con-clusion formerly arrived at by the author, that assuming the truth ofClausius's law expressing the relation between the electrical resist-ances of simple metals and their absolute temperatures, then mercurymust be considered a8 an exception. G. W. T.Thermoelectric Currents between Amalgamated Zinc andZinc Sulphate.By K. A. BRANDER (Ann. Phys. Chem. [2], 37,457-462).-The primary object of the investigation was to determinethe relation between the E.M.F. developed and the difference oftemperature between the electrodes.The electrodes, of amalgamated zinc, were placed in two vesselscommunicating by means of a siphon, and filled with a solution ofzinc sulphate. One of these vessels was kept at the temperature ofthe place of observation, while the temperature of the other wasgradually raised.The author found that, within the limits of errors of observation, theE.M.F. was proportional to the difference of temperature, until thiOEXERAL AND PHYSICAL CHENISTRT. 99difference exceeded 20.45", after which the E.M.F. appeared to increaserather more rapidly than the temperature difference.A few experi-ments were also made to determine the effect of varying the concen-tration of the zinc sulphate solution, and their results showed that theE.M.F. increased with the concentration. G. W. T.Electrochemistry and Thermochemistry of some OrganicAcids. By H. JAHN (Anla. Phys. Cliem. [2], 37,40843).B'ormic Acid.-When a solution of sodium formate in waterwas acidified with formic acid and subjected to electrolysis, i tyielded hydrogen and carbonic anhydride. The sodium saltmust first be resolved into sodium and the group HC02, theformer forming sodium hydroxide with the water of solution,whilst the latter must either break up into carbonic anhydride andhydrogen or form formic acid again with the water of solution,according to the equation 2H + CO, + H20 = 2H2C02 + 0, thefree oxygen then combining with a portion of the formic acid to formcarbonic anhydride and water.Now Bunge has shown that in theelectrolysis of formic acid no hydrogen is given off at the anode,which excludes the first explanation, and shows that a simple combus-tion of the acid takes place at the anode. The results were confirmedby determinations of the amount of gas liberated by the passage of ameasured quantity of electricity.The author made a series of determinations of the heat of combus-tion of formic acid which agreed very well together, and their meangave 62.87 cal. as the heat of combustion of a milligram mole-cule of formic acid. Thomsen obtained the value 60.2 cal., and theauthor observes that this may be considered as a very cloAe agreement,considering that, as Ostwald has shown, the heat of combustion variesconsiderably with the temperature.Acetic Acid.-A solution of sodium acetate in water was electro-lysed at the temperature 0".A considerable quantity of carbonicanhydride was formed, and after the gds given off had been freedfrom this, the residue was found to consist of hydrogen and ethane,about 65 per cent. of the former and 35 per cent. of the latter. Veryslight traces of iodoform were obtained from the liquid residue in theelectrolytic cell, From this i t follows that the action consisted inthe setting free of acetic acid at the anode, and its combinationwith the oxygen simultaneously liberated; but if this took placeentirely in the manner usually assumed, 2C2H402 = C2H, + 2C0, +H,O, the volumes of hydrogen and of ethane wodd have been equal.The excess of hydrogen present, combined with the absence of freeoxygen, shows that, part of the acetic acid must have been burntto form carbonic anhydride and water, according to the equationC2H402 + O4 = 2C02 + 2H20.In some quantitative experimentsmade with stronger currents, the proportion of hydrogen was foundto be somewhat smaller. The proportion of hydrogen present in theevolved gases was also found to diminish as the strength of thesolution wos increased. These results show that the complete com-bustion of the acetic acid to carbonic anhydride and water is favouredh 100 ABSTRACTS OF CHEMICAL PAPERS.by increasing the strength of the decomposing current, and by dimi-nishing the strength of the solution.Assuming Thornsen's values for the heats of solution required forthe calculation, the author determined the heat of combust,ion of themilligram molecule of liquid acetic acid to water and gaseous carbonicanhydride to be 208.81 cal., which is in very fair agreement with thevalues 210.3 obtained by Fabre and Silbermann, and 210.79 obtainedby Stobmann.It follows from the last result that the heat absorbedin the formation of one milligram molecule of liquid acetic acid fromamorphous carbon and water vapour is 121.61 cal.Propionic Acid.-The results obtained with acetic acid suggestedthat propionic acid would probably be resolved into normal butaneand carbonic anhydride, and t,he electrolysis of a solution of sodiumpropionate in water, acidified with propionic acid, showed that thisreaction did actually occur, but it was veiled to a considerable extentby the decomposition of part of the acid into ethylene and carbonicanhydride, evidently according to the equation C2H602 + 0 = C,H, + CO, + H20.The author considers that the results of his experi-ments with acetic and propionic acids point to the conclusion that theethane and butnnc formed during electrolysis are the results of thedecomposition of double molecules, which exist in concentrated solu-tions, but are broken up into simple molecules when the solutions arediluted.Oxalic Acid.-The electrolysis of an aqueous solution of potassiumoxalate a t the temperature 0" gave a gas consisting only of carbonicanhydride and hydrogen, so that the oxalic acid set free at the anodemust have been completely burned to carbonic anhydride and water,according to the equation H2C20, + 0 = 2C0, + H20. The heatof combustion of oxalic acid per milligram molecule was found to be74.49 oal.G. W. T.Thermochemistry of Methyl Alcohol and Solid MethylSalts. By F. STOHMANN, C. KLEBER, and H. LANGBEIN ( J . p . Ohm.[ A ] , 40, 342-364) .-The authors give details of the determinationof the following thermal values (see table, y . 101). The figures inthe sixth column represent the exces,s or deficiency of the heat ofcombustion of the methyl salt when compared with the sum of theheats of combustion of the acid from which it is formed and methylalcohol (compare Berthelot, Mhanique Chirnique, 1, 407).The authors then point out the difference bettween the heats ofcombustion of the various isomerides in this table, and also give atable showing the value of the affinity constant K (Ostwald, Abstr,,1889, 818) for 24 acids, 20 of which agree with the ruleGENERAL AND PHYSICAL CHEMISTRY.Table of thermochemical results with methyl-compounds.Methyl gallate...........Methyl P-naphthoate .....Dinrethgl phthalate (liquid)Dimethyl phthalate (solid)Substance.C&H806 ..C12HloO.: .ClQHlo04.C10H1004 .Formula.Dimethyl terephthalate ...Dimethyl oxalate. ........Dimethyl succinate (solid).,) ,, (liquid)Dimethyl fumarate ......,, citrate.........Methyl alcohol. ..........Trimethyl trimesate ......Hexamethyl mellitate.. ...Citric acid ..............C10Hl004 .C4H604 ..C&l,Od. .C6H100d..CGH,04 ..CVHI,O;. .CH,O.. ..C12H&6 .C,e131sO12.C,H,O, ..Molesularweight.15216616218418619419419419411814614614425223442619232Heat ofcumbus-tiou.Cal.896 -0€069 '31213.6801 *31402 -41120 -41113 -91117 *'71112 *2402 -1703 *6708 -5664 *71292 5983 -5.1825 -6474 *6170.6Heat offorma-tion."Cal.132 .O121 -771.4226 .770 -6164 *6171 -11'73 *3172 ,8180 *9205 -4200-5175.3249 *5345 - 5487-4365 - 461 -4101-' 0 .5-3.5-0.71-3-4-3.4- 1 . ~ 1-1.7-0.1-0.7-5.6-3-4-13.1+ 2 * 9-13 ' 8----* C = 94 Cals.; H2 = 69 Cals.A. G. B.Thermochemistry of' Nicotine. By A. COLSON (Covyt. r e d . ,109, 743-745) .--Nicoti?ze.-Heat of dissolution + 6-6 Cals. at about15" ; heat of neutralisation by hydrochloric acid, 1st equivalent =8.05 Cals. ; 2nd equivalent = 3.47 Cals. Total heat of neutyalisationby 4 mols. HC1 = 12-06 Cals. With sulphuric acid, 1st equivalent= 9.54 Cals.; total heat of neutralisation by excess of acid =13.46 Cals. It is evident that the two basic functions of nicotinehave very different energies, a fact which is also shown by colourreagents. With litrnius as indicator, nicotine has only one basicfunction, but with dimethyl-orange it Gas two.The author has also made the following determinations :-Pyridine.Piperidine.Csls. Cals.Heat of dissolution.. ................ 2.25 6-50Heat of neutralisation, 1 mol. HC1 .... 5.20 13-01- 7 , Y9 1.5 mol. HC1 . . 5.20.,Y 9 ) 13.68 1 mol. H2S04 . . -C. H. B.Apparatus for making Vapour-density Determinations underReduced Pressure. By J. F, EYKMAN (Ber., 22, 275&2758).--The author describes with the aid of diagrams an apparatus in whichvapour-density determinations may be made under reduced pressure,and in an atmosphere of hydrogen or some other indifferent g&s.The apparatus consists of it bulb-tube (A), somewhat similar i102 ABSTRACTS OF CHEMICAL PAPERS.shape to that employed in V. Meyer's method; this is heated bysome suitable vapour in the ordinary way.A weighed quantity ofthe liquid, the vapour-density of which is to be determined, is placedin a small, sealed, pipette-shaped tube, and suspended in a chamber inthe upper extremitly of the bulb-tube (A). The latter is connecteda t the top with a graduated manometer tube, placed perpendicularlyand open below, and also with a 3-way cock, so that it can beexhausted and filled with hydrogen or any other gas. The apparatushaving been completely filled with hydrogen, it is exhausted as com-pletely as pos>ible, the open end of the manometer being immersed inmercury ; the bulb-tube is then heated a t a constant temperature, andhydrogen is allowed to enter until the required pressure is obtained.As soon as no more mercury flows out of the manometer tube, thepressure is noted on the scale, and the neck of the bulb containingthe substance is broken without opening the apparatus, by an inge-nious device, so that i t drops to the bottom of the bulb-tube (A), andis there converted into vapour.The pressure is thereby increased,and the mercury which flows from the manometer tube is collected ina tared vessel ; the increase of pressure is ascertained either by weigh-ing the mercurg, the diameter of the msiiometer tube having beenpreviously determined, or from the difference in tlhe readings on themanometer scale. The vapour-densi ty is calculated from the increaseof pressure produced by the vaporisation of a known weight of thesubstance in a vessel of known volume under known conditions oftemperafure and pressure.Experiments with safrole (b.p. 232"), ethyl cinnamate (b. p. 271"),naphthylamine (b. p. 300°), phenylpropionic acid (b. p. ZOO0), andother sitbstances gave very satisfactory results.The apparatus can be employed also for making determinations byV. Meyer's method in the usual way. I?. S. K.Specific Volumes of some Ethereal Salts of the Oxalic AcidSeries. By A. WIENS (Annalen, 253, 289-318 ; compare W. Lossen,Abstr., 1888, 335).-A comparison of the molecular volumes of meta-meric ethereal salts of oxalic, malonic, succinic, and glutaric acids,containing normal alkyl radicles, shows that the larger the quantityof carbon in the acid radicle the smaller the molecular volume a t 0".This is generally the case at the boiling point also, but two exceptionswere noticed, the molecular volume of ethyl propyl malonate beingsmaller than that of ethyl succimte, and that of bntyl malonate smallerthan that of propyl butyl succinate ; these exceptions may be due tothe uncertainty of the determinations at the boiling point.The difference in molecular volume corresponding with the differencein composition increases in homologous series with the quantity ofcarbon in the compound.The difference between the molecularvolume of ethyl methyl succinate and ethyl butyl succinate, for example,is 71.3 ; that bet,ween ethyl butyl succinate and ethyl heptyl succinate,76.4. The same has been found to hold good for ethereal salts ofmonobasic acids, ethers, phenol ethers, and nlkyl iodides.A comparison of the molecular volumes a t 0" shows that an increaseby the group C'H, in the empirical formula corresponds with variouOESERAL AND PHYSICAL CHEMISTRY.103differences in molecular volume, according to the manner in whichthis increase takes place. The increase in molecular volume by theconversion of the group CnH2n+l into ( CH2)z*CnHzn+tl (excludingmethyl salts) is, on the average, 16.8 for each CH? group, but thedifference between the ethyl and methyl salts is, on the average, 18.1.The increase, due t o the conversion of the group CH2 into (CH,)., is,on the average, 16 for each additional CH2 group, but when the groupCH, is converted into CHMe (ethyl into isopropyl, for example), thecorresponding increase in molecular volume is, on the average, 17.7.The numerous experimental determinations are given in tables.F.S. I(.Absorption of Gases by Mixtures of Alcohol and Water. By0. LCBARSCH (Ann. Phys. Chem. [2], 37, 524-525).-The authorobserves that the publicat,ion of Muller's determinations of the absorp-tion of carbonic snhydride by mixtures of alcohol and water (Abstr.,1889, 816) has induced him to publish the results obtained so far inan investigation of the absorption of various gases by mixtures ofalcobol and water ; these are given in the accompanying table, showingthe percentages by volume of the gases absorbed at 20" and 760 mm.pressure by solutions containing the various percentages of alcohol(by weight) given in the first horizontal line :-Percentage ofalcohol.. ..0-00 9-09 16.67 23.08 2857 33'33 5 0 W 66.67 80~00Oxygen. .. .. 2-98 2-78 2.63 2.52 2-49 2-67 3-50 4.95 5-66Hydrogen. ,. 1-93 1.43 1.29 1-17 1.04 1.17 2.02 2.55 -Csrbonicoxide 2.41 1.87 1.75 1.68 1-50 1'94 3'20 - -The table shows that the minimum absorption for all three gasesoccurs at about the same proportion of alcohol to water, and this isthe same as that found by Muller for carbonic anhydride, and there-fore it seems probable that other gases will be found to behave in thesame way. G. W. T.Simultaneous Solubility of Sodium and Potassium Chlorides.By A. @,CARD (Compt. rend., 109, 740-743).-The sum of the saltsdissolved between -20" and +180" is represented by a straight line,yf$" = 27.0 + 0-0962t.Calculating from this coefficient the tem-perature at the limit of solubility, that is, the point at which, byreason of the increase in the proportion of salt and the decrease inthe proportion of water, the latter has disappeared, the temperatureobtained is 738", which, according to Carnelly, is the melting pointof potassium chloride.In presence of potassium chloride, the curve of solubility of sodiumcliloride between -20" and + 75" is parallel with the axis of tempera-ture. Beyond 75" it decreases, and at 97" becomes identical with thatof potassium chloride, after which it decreases to 120", and thenbecomes constant (16.7 per cent.).The solubility of potassium chloride alone is represented betwee104 ABSTRACTS OF CHEMICAL PAPERS.I-10" and + 75" by a right line with a coeficient 0.1470, and bztween75" and 180" by a second right line, which has a coefficient of 0.0793,and a limiting point at 913", or considerably above the melting pointof the salt.In presence of sodium chloride, the curve of solubility of potassiumchloride between -20" and + 75" is a right line y = 10.3 + 0.0962i ;from 75" to 120" the solubility increases rapidly, and above 120" it isrepresented by a righ't line with the same coefficient as between -20"and +75".Its limit,ing point is 913", and hence the curves of solu-bility of potassium chloride alone and in presence of sodium chlorideare not parallel, but converge to 913".At the limiting point for the mixed salts, 738", the proportion ofthe two salts would be 16.7 per cent.of sodium chloride and 83.3 percent. of potassium chloride. The total quantity of chlorine is prac-tically equal to the sum of the metals.The curve representing the quantity of chlorine in solution is a rightline ; that liepresenting the sum of the salts is also a right line ; andhence the sum of the metals is likewise represented by a right line.The curve of the chlorine and the curve of the sum of the metalsintersect at 738". C. H. B.Determination of Molecular Weights of Substances fromthe Boiling Points of their Solutions. By H, W. WILEY (Chem.News, 60,189-190) .-"The appnratus employed consisted of an oval-round bottom flask of about 200 C.C. capacity," with a side tube fromthe neck connected with a condenser to keep volume of liquidconstant.A thermometer graduated to tenths, but capable of beingread to 0.02 of a degree was employed, the bulb being enveloped infine copper foil to prevent interference of bubbles of steam. Sodiumchloride was used to determine the fkctor, the number obtained, 8.968,was used for calculating the results in the following table ; the volumeof wat)er being in all cases 150 C.C. ; the temperature of boiling waterwas 99.50" except during the experiments with sodium nitrate, whenit was 99.44".K C1. .................KBr., ................EI ...................KNO, ................E,Cr,Oj ..............NaN03 ...............Saccharose ............Oxslic acid.. ..........6 *O6 '09 '06 '018 -06 .020 *o6 .O~ _ _ _ _ _ _ _ _ _ _Total riseoftemperature.--0 '35O0 *290 *330 *330 *380 *420.200 -20~ ~~Molecular weiglit.Calculated.--76 -91123 -7163 '1108 *7283 -285.4643-2179 *4!Theoretical.74.5119 .o166 -0101 -0295 -085.0342 *O90 -0---It will be noticed that the two organic compounds give doublethe theoretical molecular weight by this method. The resultGENERAL AND PHYSICAL CHEMISTRY. 105obtained with salts containing water of crystallisation do not agreewith the molecular weights with or without this water. Theseresults were obt,ained quig independently of those of Beckman.D. A. L.Behaviour of Colloi’d Substances wlith Respect to Raoult’sLaw.By E. PATERNO (Zeit. physikal. Chem., 4, 457--461).-Thereduction of the freezing point by colloid substances in water is veryslight, and therefore leads to very high numbers for the molecularweights of such substances (Brown and Morris, Trans., 1889, 462).This, the author has observed, is the case with gallic and tannic acids ;which behave like collo’ids in aqueous solution and give molecularweights many times greater than those ordinarily accepted for thesesubstances. If, however, solutions in acetic acid are taken, thebehaviour is found to be perfectly nornial, and the reduction of thefreezing point is that corresponding with the ordinary simple mole-cular weights. Hence substances only behave as colloids towardscertain solvents, and the author holds that when a solid dissolves asa colloid, the laws of freezing are not applicable to its solutions.H. C.Can Raoult’s Method distinguish between Atomic andMolecular Union ? By R.ANSCH~~TZ (Annalen, 253, 343-347 ;compare Anschutz and Pulfrich, Abstr., 1888, 1273).-The depres-sion produced by naphthalene picrate in the freezing point of benzenecorresponds with that which would be produced by its constituentparts present together in an uncombined state. The author concludestherefore that the combination of the coniponents of naphthalenepicrate and analogous substances such as dimethyl diacetjlracemateis not dependent on atomic union in the sense of the valence theory,but on molecular union.If Raoult’s method is capable of deciding between atomic andmolecular union, it could be employed for determining the valency ofelements. F. S. I(.Kinetic Nature of Osmotic Pressure. By G. BREDIG (Zeit.physikal. Chem., 4, 444-456) .-In replying to certain objectionsraised by Pupin against the Van’t Hoff theory of osmotic pressure(Abstr., 1888, 7i8), the author develops an equation for the behaviourof a dissolved substance which is similar to that of Van der Wadsfor the behariour of gases. A special point of interest is, that accountis taken of the presence and specific attraction of the solvent. and inthis way an explanation of the mechanism of solution is obtained,which, it is claimed, is of wider application than that of Nernst (thisvol., p. 3), in which this attraction is neglected.Sphere of Action of Molecular Forces. By B. GALITZINE (Zeit.physiknl. Chem., 4, 417426).-By a process of theoretical reasoningsimilar to that already employed by Van der Waals, and using datagiven by Nadeschdin for several of the ethereal salts of the fattyacids in the critical condition, the author arrives at the conclusicsnthat the sphere of action of the molecular forces is proportional toH. C106 ABSTRACTS OF CElEMIOAL PAPERS.the masses of the attracting molecules.attraction is inversely proportional to the square of the distance.He also concludes that theH. C.Fluid Crystals. By 0. LEHMANN (Zed. physilcal. Chem., 4, 462-472).-Under the name of "fluid crystals," the author describes acbolesteryl benzoate first prepared by Reinitzer, which, althoughapparently melting at 145", behaves between 145" and 178" towardspolarised light as though still having crystalline structure. Inother respects the substance is in a perfectly liquid condition betweenthese temperatures. H. C.New Gas Burners. By M. GROGER (Zeit. any. Qhem., 1889,329-331).-These are in general form similar to Bunsen burners, butinstead of having any means of regulating the entry of air at thebottoni of the mixing tube, the top of the burner is made conical,and there is a screw arrangement by which a solid cone can be raisedwithin, so as partially to close the opening. By this means a flameof any character can be obtained, from a luminous one to oneapproaching that of a blowpipe, whilst the size of the flame can begreatly reduced without altering its character, and without risk ofits flashing down. A burner on the same principle giving a flatflame is also described. M. J. S