ELECTROLYTES IN MIXED SOLVENTS 181 



3. The Conductance of the Acids in Mixtures of the Alcohols and 

 Water. In aqueous solutions, the acids and bases occupy a unique posi- 

 tion in that their solutions possess properties which, as a rule, differen- 

 tiate them sharply from solutions of typical salts. The acids and bases 

 in water are the only electrolytes which apparently conform to the mass- 

 action law in this solvent. Furthermore, the ionization of different acids 

 and bases differs greatly, while that of salts of the same type is prac- 

 tically the same at all concentrations. So, also, the speed of the hydrogen 

 and hydroxyl ions is much greater than that of the ordinary ions at ordi- 

 nary temperatures. In the case of acids, at any rate, many facts indicate 

 an interaction between acid and water whereby a complex positive ion 

 is formed. 



In Table LXVII are given conductance values for solutions of hydro- 

 chloric acid in methyl alcohol in the presence of varying amounts of 

 water. 8 



TABLE LXVII. 



CONDUCTANCE OF HYDROCHLORIC ACID IN METHYL ALCOHOL IN THE 

 PRESENCE OF VARYING AMOUNTS OF WATER AT 25. 



A., 



The effect of adding water to a solution of hydrochloric acid in 

 methyl alcohol is to greatly decrease the conductance of the solution and 

 this effect is relatively independent of the concentration of the solute. 

 It appears, therefore, that the ionization of hydrochloric acid is not 

 materially affected by the addition of water, but that the speed of the 

 hydrogen ion is greatly reduced. It is true that on the addition of water 

 to methyl alcohol the viscosity is increased, but the viscosity change due 

 to the small amounts of water added in the case of these solutions is 

 inconsiderable and cannot account for the large decrease in the conduct- 

 ance of these solutions. Apparently, therefore, the change in conduct- 

 ance is due to a slowing up of the hydrogen ion, since it is known that 

 the chloride ion is normal in its behavior in mixtures of alcohol and 

 water. The values given for the limiting value of the equivalent con- 

 ductance are approximate, since the extrapolation function employed in 

 determining these values is uncertain. 



Goldschmidt and Thuesen, Ztschr. f. phya. Chem. 81, 32 (1913). 



