274 



Prof. J. Walker. 



[Oct. 19, 



k b /K = 1100, 



w-Amino-benzoic Acid. 



k a = 1-63 x 10- 5 , /^H 

 u 



- = 355, 



HX+,XOH- = 66. 



Even in the case of the meta-acid, where the experimental error due 

 to oxidation is greatest, the agreement is remarkably close. 



Where the ionised proportion is great, i.e., where u is no longer 

 approximately equal to ?/, the evaluation of the concentrations of the 

 various components in the solution is troublesome. In order that for 

 any case likely to occur, an idea of the magnitude of u may be 

 obtained, I append a table which gives values of u/rj = uv, i.e., of the 

 unionised proportion of the electrolyte, under a considerable number of 

 different conditions. 



uv = uh for k a = 10~ 4 . 



It will be noted that the preceding table only gives w for the acid 

 constant k a = 10~ 4 . From the table it is not, however, difficult to 

 find w for other values of k a . If, for example, it is desired to find v 

 for a given value of u, we may make use of the following relation, r 

 being used to denote the ratio k b /K : 



Now, if we consider another amphoteric electrolyte with another 

 k at but the same &&, we have 



v{ -u = a' (l+2ru), 



