Question

Hey !!

Why is dioxygen is gas but sulphur is a solid ?

No Lazy answers.

Answer 1

Sulphur goes extensive between its molecules. They are normally found as Monoclinic and Rhombhic SUlphur at room temperature. On the Other hand, Oxygen exists as a diatomic species. Hence there is no extensive forces between them. Only few weak Van-der waals force is present. Hence following reason can be attributed for why Sulphur is a solid while Oxygen is gas:

1. Increased Van-der-Waals force in sulphur than OXygen due to increase in size of Sulphur.

2. Sulphur exists as S8 molecule found normally as a crystalline solid at room temperature while there is no such phenomenon in OXygen.

Hence Sulphur exists as solid while Oxygen exists as gas at room temperature , being in the same group

Answer 2

Hi,

Here is your answer,

Due to small size and high electronegativity, oxygen forms pπ - pπ multiple bonds. So, As a result, oxygen exists as diatomic (O₂) molecules. These molecules are held together by weak ''VAN DER WAALS'' forces of attraction which can be easily overcome by collisions of the molecules at room temperature. So, therefore O₂ is a gas at room temperature .

Sulphur, on the other hand because size and lower electronegativity, does not form pπ - pπ multiple bonds. Instead, it prefers to form S-S single bonds. Further, because of stronger S-S than O-O single bonds, sulphur has a much greater tendency for catenation and lower tendency for pπ-pπ multiple BondS, forms octa-atomic (S₈) molecules having eight-membered puckered ring structure. Because of bigger size, the forces of attraction holding the S₈ molecules together are much stronger which cannot be overcome by collisions of molecules at room temperature.

SULPHUR IS A SOLID AT ROOM TEMPERATURE.

Hope it helps you !