The acid hydrolysis of methyl acetate is a pseudo
first order reaction. The reaction mixture (2 mL)
was titrated with alkali (0-5 M) as a function of
time. The data is given below :
Time (s) 0.600 1200 2400
Vol. of alkali
| 16-3 17-2 181 19-
0 26-2
used (cm3)
oo
Calculate the rate constant.
Answers
Answer:This may help you
Explanation:
The hydrolysis of ethyl acetate in presence of alkali (saponification) has been reported using a pH meter1. However the experimental details are not available. The saponification reaction has also been reported by using titration method in which HClwas used to arrest the reaction2or acetic acid was used to arrest the reaction.The reported values of specific reaction rate constant k determined by conductometric method3-6by different investigators are significantly different. The authors of the present articles have studied the kinetics of saponification of ethyl acetate using pH meter and titration method.
In the solution of high Na+ ion concentration the observed pH using glass combination pH electrode is less than the true pH of the solution and this is termed as alkaline error.7,8 In the pH method reported here the true pH of the reaction mixture was calculated by considering the “alkaline error”. The pH method has so far not been reported by using the “true pH” for the calculation of H+ ion concentration and OH- ion concentration of the reaction mixture. A significant difference in the reaction rate constant k calculated by using the alkaline error correction and that calculated without using the correction was observed. For comparison purpose the saponification of ethyl acetate was also investigate at room temperature using the titration method and is reported here.