SCIENCE 



[Vol. LVI, No. 1460 



THE AMERICAN CHEMICAL 

 SOCIETY 



DIVLSION 01' PHYSICAL AND ORGANIC CHEMISTRY 



(Continued from Novem'ber 17) 

 The eondiictivities, viscosities and densities of 

 solutions of mixed electrolytes. (Xiantern) : C. E. 

 Ruby and J. Kawai. 



The mutual solubility of liquids: Two new 

 methods for determining the same: Arthur E. 

 Hill. The published results on the solubility of 

 liquids are meagre compared with the voluminous 

 data on the solubility of sclids. It is proposed to 

 studj' a number of new cases, and repeat some 

 determinations which appear to be inaccurate. 

 No methods have proved to be of universal ap- 

 plicability. In place of the terms synthetic and 

 analytic methods, which do not indicate the essen- 

 tial differences in procedure, the term thermo- 

 static is proposed for metJiods in which the tem- 

 perature is held constant and plothostatic 

 for methods in wliich the concentration is 

 fixed and the temperature changed to the 

 point of beginning heterogeneity or homo- 

 geneity. As a new thermostartie method suitable 

 to liquids of moderate solubility, tie measure- 

 ment of the volumes obtained in suitable vol- 

 umetric apparatus in two experiments may be 

 used, on the basis of the phase rule, to calculate 

 the solubilities. An accurate determination of the 

 solubility curves for ether and water has been 

 made by this method. Eor liquids dissolving 

 very small amounts of water the use of silver per- 

 chlorate is proposed; the BoluibiHtj' of this salt 

 rises sharply with the presence of small amounts 

 of water, so that, after establishment of a refer- 

 ence curve at a standard temperature (35°), the 

 solubility of water at any other temperature can 

 be determined. The solubility of water in ben- 

 zene and in aniline lias been measured by this 

 second method. 



The occurrence of closed sohiliility curves in 

 three-component systems: Arthur E. Hill. 

 Closed solubility curves have been found in sev- 

 eral tvfo-coiniponent systems, such as nicotine and 

 water. Among three-component systems the 

 closed curve lias been found only once, in the case 

 of silver perehlorate, water-benzene, recently pub- 

 lished by the author. The same type of curve 

 has now been found in the system silver per- 

 chlorate-v/ater-toluene, and exists from room tem- 

 perature to some temperature above 100°. 

 In both these cases, the curve for the two 

 component systems (silver perchlorate-benzene 

 and silver perchlorate-toluene) approaches a 

 perpendicular to the temperature axis, i. e., 



tie two components just fail of breaking 

 into two liquids ; the addition of the third 

 component evidently decreases the mutual solu- 

 bility, causing the formation of two liquid phases. 

 It is well known that, when there is limited solu- 

 bility of two liquids, a third component may 

 either increase or decrease .that solubility. Where 

 there is unlimited solubility of two components 

 in the fused state (i. e., only one liquid phase 

 exists), the addition of the third component 

 should again act either to increase or decrease 

 miscibility; but if the two-component system 

 shows a nearly perpendicular curve, indicating 

 that the forces existing are only just sufficient to 

 hold the two components in solurtion, a tliird com- 

 ponent clhosen to reduce mutual solubility should 

 result in a separation into two liquid phases, 

 which, in the three-component diagram, leads to a 

 closed curve. We may therefore look for closed 

 curves in three-component systems most hope- 

 fully where one of the two-component systems 

 shows a solubilitj' curve of the type described. 



Soliibilities up to the critical temperature: 

 P. A. Bond and M. G. Waddell. I — Methods of 

 manipulation. II — Solubilities in sulfur dioxide 

 at 25° G. A method for determining solubilities 

 up to the critical temperature has been devel- 

 oped. Tlie apiparatus and method of maniDulia- 

 tion are discussed. Solubilities in sulfur dioxide 

 at 25° C. have been determined for salts of 

 potassium, silver, cadmium, tin, antimony, tellu- 

 rium, manganese and in one ease for Ba as the 

 thiocyanate. Aside from the solubilities as de- 

 termined, interesting reactions between sulfur 

 dioxide and chlorates, bromates, iodates and 

 nitrates were noticed. Also a double layer was 

 formed in the case of SnBr. Work is to be con- 

 tinued until salts of all metals have been tried, 

 and in eases where solubility is shown is to be _ 

 carried on at different tempera/ture levels. 



Vapor pressures of certain hydrated sulfates : 

 Clifford D. Carpenter and Eric E. Jette. The 

 vapor pressures of some of the hydrated sulfates 

 of Cu, Mn, Mg, Co, and Cd have been studied 

 at a number of temperaitures belov/ the transition 

 points, and tlie saturated solutions of some of 

 them at several temperatures above these points. 

 Some of the determinations have been carried as 

 high as 90° C. A modiiieation of the Bremer- 

 Frowe tensimeter was used. All points were 

 determined by approaching equilibrium from 

 both a higher and a lower pressure. A special 

 thermostat was constructed for tie higher tem- 

 peratures. The results obtained have been used 

 in plotting the vapor pressure curves, in calcu- 

 lating the heats of vaporization, and for plotting 



