Question

Rhombic and monoclinic sulphur are:
(A) Isomers of sulphur
(B) Isotopes of sulphur
(C) Allotropes of sulphur
(D) Isobars of sulphur

Answer 1

Hint :Sulphur is needed for all living things, but it is almost always found in the form of organosulfur compounds or metal sulphides. Organosulfur compounds include three amino acids (cysteine, cystine, and methionine) and two vitamins (biotin and thiamine). It is a non-metal that is produced as a byproduct of natural gas processing.

Complete Step By Step Answer:
Sulphur exists in a variety of allotropes. Some of them include yellow rhombic sulphur (-sulphur) and monoclinic (-sulphur). The most intriguing characteristic is their thermal stability; the allotropes of sulphur are interconvertible, i.e., rhombic sulphur becomes monoclinic sulphur when heated above ${\text{396K}}$.
Sulphur allotropes include rhombic and monoclinic sulphur. Allotropy, also known as allotropes of the elements, is the property of certain chemical elements to occur in two or more distinct forms in the same physical state. Allotropes, on the other hand, have different chemical properties.
Rhombic sulphur is octahedral in form and crystalline in nature. As rhombic sulphur is melted in a dish and then cooled, monoclinic sulphur is obtained. We make two holes in the crust and pour out the remaining liquid in this process. When the crust is extracted, we get colourless needle-shaped crystals of $\beta $-sulphur.
Rhombic sulphur exists as rhombic octahedral crystals and is the most stable allotropic type of sulphur, while monoclinic sulphur exists as long, needle-shaped prisms and is only stable at temperatures between $96$ and $119$degrees Celsius.
Hence, Rhombic and monoclinic sulphur are allotropes of sulphur. So, the correct option is (C).

Note :
Since both allotropes of sulphur are stable at ${\text{369K}}$, it is referred to as the transition temperature. To put it another way, we can say that $\alpha \, - \,$sulphur is stable below ${\text{369}}\,{\text{K}}$ and becomes $\beta $-sulphur above that temperature. $S8$ molecules are found in both rhombic and monoclinic sulphur. $S8$ molecules are packed in various ways, resulting in different crystal structures.