MIXTURES OF ELECTROLYTES. M C IXTOSH. 127 



It will be noticed that the ratios in the above table are not the 

 same for all solutions, but are practically the same for solutions 

 of both salts of the same conductivity. The variation of the 

 ratio may have been due to some unknown defect of apparatus 

 or mode of using it ; but as this source of error was equally 

 operative in the case of solutions of both salts of the same 

 conductivity, it would probably be equally operative also in 

 mixtures of the same conductivity. Hence in reducing the 

 observed conductivity of a mixture of potassium and sodium 

 chloride solutions to Kohlrausch's standard, the factor employed 

 was the value of the ratio for the conductivity which the mixture 

 was found to have, this ratio being determined from the above 

 table by graphical interpolation. Bender found a similar 

 variation in the ratio of his conductivities of solutions of these 

 salts to Kohlrausch's conductivities for solutions of the same 

 strength. 



On comparing the observed conductivities of solutions of 

 hydrochloric acid with conductivities of solutions of equal concen- 

 tration, as given by Kohlrausch, the ratios were found to be 

 practically uniform and equal to 0.955. In the tables which 

 follow all conductivities are expressed in terms of Kohlrausch's 

 standard. 



Conductivities of the Simple Solutions. 



In order to obtain the data for the calculations, it is necessary 

 to draw curves giving the relation of the dilution to the concen- 

 tration of ions in the simple solutions, and therefore to know 

 the concentrations and conductivities of sufficiently extended 

 series of these solutions. In the case of sodium and potassium 

 chlorides sufficient data were available for this purpose in 

 Kohlrausch's observations. The following tables give the dilu- 

 tions and ionic concentrations of solutions of these salts examined 

 by him. 



