Question

A yellow crystalline allotropic form of sulphur ($A$) on heating at $X^{o}C$ converts to another allotropic sulphur ($B$) that has needle shape. Identify $A,B,X$.

Answer 1

When rhombic sulfur is heated above $95.8℃$ it changes form into monoclinic sulfur. When cooled below $95.8°C$ it reverts to rhombic sulfur.

A - rhombic sulfur

B - monoclinic sulfur

X - $95.8°C$