ALBUMIN: THE ISO-ELECTRIC REACTION 27 



than basic in character, that such bodies will be amphoteric 

 electrolytes with K a > K & . 



The following table gives the dissociation constants of some 

 ammo-acids and di-peptides, and, for comparison, those of a 

 few weak acids and bases which are occasionally used : 



Table 5. 

 Dissociation Constants at 25 



(when not otherwise stated). 



Without treating the question exhaustively we can discuss 

 on the basis of this table the relation of the dissociation con- 

 stants to the constitution of the amino-acids, which is not 

 without importance for the proteins. 



Glycin, alanin, and leucin have the same K, and their 

 slightly different basic dissociation constants are of the same 



