Question

why is dioxygen a gas while sulphur is a solid

Answer 1

Intermolecular forces in dioxygen are weak van der Walls which cause it to exist as gas. Whereas sulphur can't form pπ– pπ bonds and has puckered ring structure held together by covalent bonds .So it is solid.

Answer 2

Hey !!

It is because of its small size, oxygen is capable of forming pπ - pπ bond and exists as diatomic O₂ molecule. The intermolecular forces in oxygen are weak van der Waals force, due to which it is a gas at room temperature. On the other hand, sulphur, due to its larger size prefers to form S - S single bond and exist as octaatomic S₈ molecule puckered ring structure. Because of larger size the force of attraction holding the S₈ molecules together are much stronger. Hence sulphur is a solid at room temperature.

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