Question

Is ${IC{l}_2}^{-}$ nonpolar or polar?

Answer 1

The molecule has two identical non-central atoms.The structure is linear, giving dipoles that are opposite in direction to each other. The three lone pairs of electrons are ${120}^o$ away from each adjacent one, a rotationally-symmetric configuration; so, the lone-pair-bonding-pair repulsions sum to cancel out as well it doesn't matter what the electronegativity difference is between Cl and I; the dipoles all cancel out to give a net dipole moment of 0 in all directions.
Therefore , $IC{l}_2^{-}$ is projected to be nonpolar.