1904.] 



Theory of Amphoteric Electrolytes. 



273 



following improved method of ascertaining the value of the constant 

 k a , which is here not readily accessible to direct experiment, may be 

 noted. Previously this value was adjusted to correspond with the 

 experimental value of -obtained at ^=1024, the greatest dilution 

 investigated, for in the cases under consideration the constants & and 

 k a approximated most closely at this degree of dilution. This 

 advantage, however, is more than counterbalanced by the drawback 

 that here the experimental errors due to conductivity of the water, 

 oxidation at the electrodes, etc., are at a maximum. In the recalcula- 

 tion, therefore, the adjustment of the k a value was made from a 

 consideration of the most concentrated instead of the most dilute 

 solutions in order that the effect of these experimental errors might, 

 as far as possible, be eliminated. This readjustment has in every case 

 improved the concordance between the experimental and theoretical 

 values of the conductivity, as a comparison of the subjoined tables 

 with those previously given (pp. 164-5) will show. 



0-Amino-benzoic Acid. 



k b /K = 112, k a = 1-04 x 10- 5 , /^H 

 /^HX+,XOH- = 70. 



- = 357, 



jp-Amino-benzoic Acid. 



fe/K = 210, k a = 1-21 x 10- 5 , /^H 

 ii HX + ,XOH- = 68. 



- = 356, 



