ELECTROLYTES IN MIXED SOLVENTS 183 



This is further indicated by results at higher concentrations of water. 

 In the following table are given values for the conductance of hydro- 

 chloric acid in mixtures of water and ethyl alcohol at 25 for larger 

 amounts of water. 5 



TABLE LXIX. 



CONDUCTANCE OP SOLUTIONS OF HYDROCHLORIC ACID IN ALCOHOL IN THE 

 PRESENCE OF WATER AT 25. 



Equivalent Conductances at Dilutions 

 C H 2 F = 12 F = 48 F=oo 



0.0 34.3 43.6 67. 



6.83 37.2 43.0 51. 



13.85 60.3 65.8 75.5 



27.68 115. 121. 130. 



41.57 207. 218. 230.5 



The values for the pure solvent do not agree with those given in Table 

 LXVIII. It is possible that the values in this case are low owing to 

 the presence of traces of water. 6 However, it is evident that, in the 

 presence of water at higher concentrations, the conductance increases with 

 addition of water. This may be due, in part, to an increased ionization, 

 but it appears probable that it is also in part due to an increase in the 

 speed of the hydrogen ion. That a complex between water and the 

 hydrogen ions is initially formed is likewise indicated by other prop- 

 erties of these solutions such as the catalytic effects due to the hydro- 

 gen ion. 7 



In the case of the weaker acids, on addition of water, the conductance 

 curve is modified the more the weaker the acid. In Table LXX are given 

 values for the conductance of sulphosalicylic acid in ethyl alcohol. 8 In 

 solutions of sulphosalicylic acid, there is a marked decrease in the con- 

 ductance on addition of small quantities of water up to normal concen- 

 tration, but the effect is not as great as it is in solutions of hydrochloric 

 acid. 



TABLE LXX. 



CONDUCTANCE OF SULPHOSALICYLIC ACID IN C 2 H 5 OH AT 25 IN THE 

 PRESENCE OF WATER. V = 160. 



C HQ .... .003 .019 .1 .2 .5 1.0 



49.0 49.0 45.4 37.0 32.8 29.9 29.5 



"Kailan, Ztsclw. /. phys. Cliem. 89, 678 (1914). 

 Kailan, loc. cit. 



7 Goldschmidt and Thuesen, loc. cit. f p. 62. 



8 Goldschmidt, Ztschr. f. phys. Chem. 89, 139 (1914). 



