(N/A) Haloarenes undergo electrophilic substitution reactions like halogenation,nitration,sulfonation,and Friedel-Crafts reactions at the ortho and para positions because the halogen atom is an $o,p$-directing group. The resonance structures of halobenzene are shown in the image.
In these structures,the electron density is higher at the ortho and para positions due to the negative charge. Consequently,the electrophile attacks the ortho and para positions of the haloarene. The $-X$ group is $o,p$-directing,and electrophilic substitution occurs at these positions.
However,haloarenes are less reactive than benzene towards electrophilic substitution. The halogen atom $(X)$ exerts an electron-withdrawing inductive effect $(-I)$.
Due to this,the halogen atom pulls electrons from the benzene ring towards itself,resulting in lower electron density in the halobenzene ring compared to benzene. Thus,haloarenes are less reactive than benzene,making their electrophilic substitution reactions slower and requiring more vigorous conditions.