Use their electronegativies.
Cl-Cl would be nonpolar because they will share the electrons equally.
C-Cl should be polar.
Would a C-Cl bond be polar or nonpolar in a molecule if both have a formal charge of 0?
I thought at first that it would be polar just due to their electronegativities (just by looking at the periodic table), but if they both have a formal charge of 0, does that make it a nonpolar bond or does formal charge not really matter?
2 answers
I agree with John1. Look at CCl4. In CCl4 both C and Cl have zero formal charge; however, each C-Cl bond is polar. The CCl4 MOLECULE is symmetrical; therefore, it is non-polar but that's because each of the C-Cl polar bonds cancel each other because of the symmetry of the molecule.