Action of Hydrated and Nonhydrated Salts on Saponification. 87 



reverse order of their stability. The curves plotted with time and 

 percentage hydrolysis as axes are of the same general character, with a 

 concentration of maximum accelerating power, which is 1.8 normal for 

 potassium chloride, 0.5 normal for potassium bromide, and 0.25 normal 

 for potassium iodide. Abnormally low results were found with potas- 

 sium iodide, which he explained as due to the decomposition of the 

 potassium iodate present by the acetic acid formed in the reaction 



KI0 3 + 6KI + 6CH 3 COOH > KI +3I 2 +6CH 3 COOK +3H 2 



These solutions were found to be slightly colored, due to the iodine 

 set free. By varying the time, Kellogg studied the reaction from the 

 point where 1 per cent of the ester was hydrolyzed to practically com- 

 plete hydrolysis. The salt has two effects, the one in dilute solution 

 being accelerating, the other increasing as the concentration increases, 

 retarding the reaction. 



Kellogg made three suggestions to explain this phenomenon. One 

 hypothesis is that the accelerating effect is due to the ionized salt 

 and the retardation is due to the undissociated salt. This would 

 explain the decreasing acceleration with increasing concentration, as 

 the ionized part increases slowly in proportion to the non-ionized part. 

 It would also account for the facts found by the earlier investigators, 

 that the salt of an acid has the greatest effect with dilute acids, since 

 with a dilute acid we have a smaller number of common ions and 

 therefore a greater dissociation of the salt. 



Kellogg also stated that the two effects might be functions of the 

 ions; one of the potassium, the other of the halogen ion. This would 

 account for the difference between the three salts which he used, but 

 not for the difference between weak and strong solutions. 



Euler's 1 suggestion would explain the dual effect. He assumes that 

 the salt increases the reactive capacity of the water; the ions of the 

 neutral salt combining with the solvent. The water around the ion 



of the salt is at a high tension, and we therefore would have a large 



+ 

 number of H and OH ions. This would explain the larger effect of 



neutral salts with dilute acids. Spohr and Arrhenius held practically 

 the same views as Euler. 



Euler also suggested that intermediate compounds might be formed. 



Arrhenius' s older idea of the "active" and " inactive" forms of the 

 ester would explain all of the facts, the salt disturbing the equilibrium 

 in favor of the " active" form. 



In conclusion, Kellogg stated that no one theory could explain all 

 of the facts, each having its merits and its disadvantages. 



Henderson and Kellogg, 2 continuing the work of Kellogg, studied the 

 chlorides of sodium, lithium, calcium, strontium, and barium, and the 



it. phys. Chem., 32, 348 (1900). 2 Journ. Amer. Chem. Soc., 35, 390 (1913). 



