Why SO2 polar but SO3 is non polar?

Answer 1

SO2 has a bent molecular geometry such that you can say there is an oxygen end and a Sulfur end in the molecule. Because of this, the pull that the oxygen atoms exert on the electrons results in a net dipole moment.

By contrast SO3 has a trigonal planar geometry. The oxygen atoms are arranged in a perfectly symmetrical arrangement around the central sulfur atom. As a result, the polarities of the 3 sulfur-oxygen bonds cancel each other out.

Answer 2

SO2 is polar because it has a bent molecular geometry with the sulfur atom at the center and two oxygen atoms bonded asymmetrically, creating a net dipole moment. In contrast, SO3 is nonpolar because it has a trigonal planar molecular geometry with the sulfur atom at the center and three oxygen atoms bonded symmetrically, resulting in a cancellation of dipole moments.