The decreasing order of the rate of alkaline | vedclass

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(A) The rate of alkaline hydrolysis of esters depends on the electrophilicity of the carbonyl carbon.Electron-withdrawing groups $(EWG)$ increase the

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$III > II > I > IV$

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(A) The rate of alkaline hydrolysis of esters depends on the electrophilicity of the carbonyl carbon.Electron-withdrawing groups $(EWG)$ increase the electrophilicity of the carbonyl carbon,thereby increasing the rate of nucleophilic attack by $OH^-$.Electron-donating groups $(EDG)$ decrease the electrophilicity,thereby decreasing the rate.The substituents at the para-position are:$III: -NO_2$ (Strong $EWG$,$-I$ and $-M$ effect)$II: -Cl$ ($EWG$,$-I$ effect > $+M$ effect)$I: -H$ (Reference)$IV: -OCH_3$ (Strong $EDG$,$+M$ effect > $-I$ effect)The order of electron-withdrawing strength is $-NO_2 > -Cl > -H > -OCH_3$.Therefore,the decreasing order of the rate of alkaline hydrolysis is $III > II > I > IV$.

The decreasing order of the rate of alkaline hydrolysis for the following esters is:
$I: C_6H_5COOC_2H_5$
$II: p-Cl-C_6H_4COOC_2H_5$
$III: p-NO_2-C_6H_4COOC_2H_5$
$IV: p-CH_3O-C_6H_4COOC_2H_5$

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The decreasing order of the rate of alkaline hydrolysis for the following esters is:$I: C_6H_5COOC_2H_5$$II: p-Cl-C_6H_4COOC_2H_5$$III: p-NO_2-C_6H_4COOC_2H_5$$IV: p-CH_3O-C_6H_4COOC_2H_5$