Explain each of the following observations:
(iv) The `-C""Cl_3` group is a m-directing group, even though the carbon atom is not bonded to a more electronegative atom by a double or triple bond.

Explanation

`-C""Cl_3` is an electron withdrawing group because of its -I effect which is attributed to the presence of three highly electronegative Cl- atoms.
Consequently it decreases the electron density of the benzene ring especially at the ortho- and para- positions.
So, `-C""Cl_3` is a deactivating group which makes the ring less reactive towards electrophilic substitution and substitution occurs preferably at meta-positions.