Although chlorine is an electron withdrawing group, yet it is ortho – , para – directing in electrophilic aromatic substitution reaction. Explain why it is so?

Chlorine, as a relatively electronegative element, withdraws electrons via the – I effect and donates electrons via resonance (+R).
We know that resonance rules over inductive in most cases, but in the case of halogens, inductive rules. As a result, chlorine is slightly electron withdrawing via inductive, yet it acts as an Ortho, Para directing group due to the presence of a lone pair.
One of chlorine’s lone pair of electrons can conjugate to the ring, directing the electrophile to the ring’s ortho and para locations.

Final Answer:-
For electron donating (through resonance) groups like chlorine, resonance increases electron density in the ortho and para positions.