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the second effect predominates over the first and the velocity coeffi- 
cient instead of decreasing, increases with the concentration of 
sodium picrate. 
Moreover WarpeN has shown that there are two types of salts 
with regard to their effects on the di-electric constant of the solvent. 
He has observed that N(CH,),Cl markedly increases the di-electric 
constant of the solvent, whilst CH,NH,HCI affects this constant to 
a very slight extent. It is quite possible that even in aqueous solution 
salts like potassium oxalate, sodium acetate, etc. do not increase 
appreciably the ionising power of the solvent and the velocity of 
the reaction in its presence does not increase. In this way we can 
explain the negative effect of potassium oxalate and positive effect 
of sodium picrate on ester hydrolysis from the point of view of the 
change of the di-electric constant of the solvent due to the dissolution 
of electrolytes. 
SUMMARY. 
a. The hydrolysis of methyl acetate was investigated in presence 
of oxalic acid and pierie acid and sodium picrate. In the former case, 
the velocity coefficient falls off, whilst in the case of picric acid, 
the velocity coefficient increases with the concentration of sodium 
picrate up to a certain extent and then decreases with the increase 
of the concentration of sodium picrate. 
6. An explanation of these results is suggested on the basis of the 
increase of the di-electric constant and ionising power of the solvent 
observed by Watprn when salts are dissolved in it. 
Chemical Laboratory Muir Central College, 
Allahabad, India. 
