CBSE Class 10 Answered

Sulphur dioxide:

Sulphur has 6 electrons in its outer level, and the oxygen atoms between them contribute another 4 (1 for each bond). That gives 10 electrons in total 5 pairs. 4 pairs are needed for the bonds, leaving 1 lone pair. Each double bond uses 2 bond pairs and can be thought of as a single unit.

There are 2 double bond units and 1 lone pair, which will try to get as far apart as possible – taking up a trigonal planar arrangement.

Because the lone pair isn’t counted when you describe the shape, SO₂ is described as bent or V-shaped.

Carbon monoxide:

Carbon monoxide can be thought of as having two ordinary covalent bonds between the carbon and the oxygen atoms plus a co-ordinate bond using a lone pair on the oxygen atom.