What is the VSEPR shape of SO_2?

1 Answer
Mar 21, 2016

The molecule is bent around the central sulfur, with an /_O-S-O = <120""^@.

Explanation:

There are 18 valence electrons to distribute around the molecule; and the least electronegative atom, sulfur, is ASSUMED to be central.

Resonance structures of ""^(-)O-S^(+)=O and ""^(-)O-S^(2+)-O^- are valid. In either case there are 3 regions of electron density around the central sulfur: a lone pair, and 2xxS-O bonds, The electronic geometry should be based on a trigonal plane. But, because we describe molecular geometry on the basis of bonds not electron pairs, we describe the geometry of SO_2 as bent. The actual molecule has /_O-S-O = 119""^@.