JACQUES LOEB 



409 



We can, therefore, state that sodium acetate has the same effect on 

 the viscosity of gelatin chloride as the addition of any other salt with 

 monovalent anion, and that the anomalous effect ascribed to the ace- 

 tate anion in the colloidal literature is in reality due to the depression 

 of the hydrogen ion concentration of the gelatin solution by the Na 



1d 55 

 cr> 50 



o 



CP 



o 



I 



45 

 40 

 35 

 30 

 25 

 20 

 15 

 10 

 5 

 







8192 4096 2048 1024 512 256 128 64 32 16 8 



Concentration 



Fig. 11. Showing that the depressing effect of salts with monovalent anion on 

 the swelling of gelatin chloride of pH 3.3 is similar to that on the specific viscosity. 

 All salts with monovalent anion depress the swelling of gelatin chloride to the 

 same extent, the seeming deviation from this rule being due to variation in the 

 pH of the gelatin solution caused by buffer salts. 



acetate which is a buffer salt. The failure to recognize the buffer 

 character of salts, like the acetates, citrates, and tartrates, has led 

 to the error of the Hofmeister ion series. In reality we find our val- 

 ency rule confirmed whereby all salts with an anion of the same 

 valency have the same relative depressing effect on the viscosity of a 

 gelatin chloride solution if the pH of the solution is kept constant. 



