Section 55. Change of Conductance with Concentration. 139 



55. CHANGE OF THE EQUIVALENT CONDUCTANCE WITH THE 

 CONCENTRATION AND TEMPERATURE. 

 The change of the conductance with the concentration may be first 

 discussed. In the case of the sodium acetate values uncorrected for hydrol- 

 ysis there is, owing to this phenomenon, an abnormally large increase 

 between the highest and lowest concentrations, especially at the higher 

 temperatures. Moreover, it is not probable that the values corrected for 

 hydrolysis are as accurate as those for unhydrolyzed salts. This makes it 

 scarcely worth while to investigate fully the form of function applicable 

 to the change of conductivity with the concentration in the case of this 

 salt. Of much interest, however, is such a study in the case of hydro- 

 chloric acid, especially with reference to the conformity of its behavior to 

 that of the neutral salts. We have therefore tested the applicability to the 

 data of the three functions A A = KC h (Kohlrausch), A A = 

 KOA* (Barmwater), and A A =/CiC* (van't Hoff), by plotting the 

 values of A along one co-ordinate axis and those of C i , A i C i , or A*C* along 

 the other axis, drawing the best representative straight line through the 

 points in such a way as to make the percentage deviations of the two con- 

 ductivity values for the more concentrated solutions (10 and 100 or 10 

 and 85 milli-normal) and also of those for the more dilute solutions oppo- 

 site and equal, and reading off the deviations of the separate points from 

 the line. These deviations, expressed as percentages of the conductance 

 values, are given in table 38. 



Table 38. Deviation of the observed conductance values for hydrochloric 

 acid from those calculated by various empirical formulas. 



