Question

Explain the following observation:

Sulphur in vapour state exhibits paramagnetic behaviour.

Answer 1

Sulphur in vapour state exhibits paramagnetic behaviour because:

1. In vapour state, sulphur exists as S₈ molecules, which can dissociate into smaller molecules or atoms.
2. Some of these smaller species have unpaired electrons.
3. The presence of unpaired electrons leads to paramagnetism.
4. Molecular orbital theory explains this by showing that not all electrons remain paired in gaseous sulphur species.

Hence, paramagnetism arises due to unpaired electrons in sulphur vapour.