Solution:
Solution
The hydrolysis of acid chloride involves a nucleophilic attack on the fairly positive carbon atom by one of the lone pairs on the oxygen of a water molecule.
$$PhCOCl + H_2O \rightarrow PhCOOH + HCl$$
More positive carbon will be more reactive for the attack. Presence of $$-NO_2$$ which has $$-M$$ effect makes the $$C$$ of $$p-NO_2C_6H_4COCl$$ more positive and most reactive. $$OCH_3$$ with $$+M$$ effect makes the $$C$$ less positive and less reactive.
Therefore the order of reactivity is $$ p−O_2NC_6H_4COCl>PhCOCl>p-CH_3OC_6H_4COCl$$
