Describe the reaction of chlorobenzene with a hydroxyl group (nucleophilic substitution).

(N/A) Chlorobenzene is extremely resistant to nucleophilic substitution due to the partial double bond character of the $C-Cl$ bond and the instability of the phenyl cation. However,it can be converted into phenol by heating with aqueous sodium hydroxide $(NaOH)$ at a high temperature of $623 \ K$ and a high pressure of $300 \ atm$,followed by acidification.
The reaction is as follows:
$C_6H_5Cl + NaOH \xrightarrow{623 \ K, 300 \ atm} C_6H_5ONa + H_2O$
$C_6H_5ONa + H^+ \rightarrow C_6H_5OH + Na^+$
The presence of electron-withdrawing groups like $-NO_2$ at ortho- and para-positions significantly increases the reactivity of haloarenes towards nucleophilic substitution by stabilizing the carbanion intermediate.