AIPMT 2010 Physics and Chemistry Paper

Lesser the electron density of acyl carbon atom, more will be the susceptiblity of nucleophile to attack it. The Cl atom has strong −l effect because of the weak p-bond between the small sized C-atom and large sized Cl atom. Thus in CH3‌COCl, acyl carbon has least electron density and hence, more suceptible for nucleophilic attack.