Question

From the two allotropes of sulphur, Rhombic sulphur and Monoclinic sulphur, which is more stable?

• A. Rhombic
• B. Monoclinic
• C. Both are equally stable
• D. None

Answer 1

Answer: (A)

Rhombic sulphur or $\alpha$ sulphur is yellow solid consisting of $S_8$ puckered rings. The thermodynamically stable form at ordinary temperatures.
Monoclinic sulphur is a yellow crystalline solid, consisting of $S_8$ puckered rings. Only stable above ${95.6}^{o}C$, it reverts to $\alpha$-sulphur at room temperature.