Question

Which of the following options regarding sulphur is correct?
(a) Density of monoclinic sulphur is more than rhombic sulphur due to the arrangement of puckered rings.
(b) In a puckered ring one sulphur is bonded with 2 other sulphur atoms.
(c) The melting point of rhombic sulphur is considered as the transition temperature of sulphur.
(d) Flower of sulphur is the vapour form of sulphur.
A.only b
B.a and b
C.b and e
D.a, b and d

Answer 1

No other element forms more solid allotropes than sulphur. The ability of sulphur to form chains is displayed in the allotropes of the element and in a variety of compounds built up of sulphur chains terminated by other atoms or groups. Sulphur allotropes are known of which the most common forms found in nature are the greenish-yellow orthorhombic Rhombic Sulphur. (α-sulphur), consisting of puckered rings of S8S8 and Monoclinic Sulphur (β-sulphur), which is a yellow crystalline solid, containing ${S_8}$ puckered rings.

Complete step by step answer:
(a) Monoclinic sulphur has a density of $2.01\dfrac{g}{{c{m^3}}}$ (α-sulphur $2.069\dfrac{g}{{c{m^3}}}$), while Rhombic Sulphur has a density of $2.06\dfrac{g}{{ml}}$. Hence, the density of rhombic sulphur is more than monoclinic sulphur and the statement (a) is wrong.
(b) We know that, in a puckered ring one sulphur is bonded with 2 other sulphur atoms. Thus, the statement (b) is correct.
(c) Rhombic sulphur melts at about ${118^0}C$, while its transition temperature is ${95.6^0}C$. The melting point and transition temperature of sulphur are different. Thus, the statement (c) is also wrong.
(d) Flower of sulphur is not the vapour form of sulphur. It is a bright-yellow powdered form of sulphur. Thus, the statement (d) is also wrong.
Therefore, options (a), (c) and (d) are wrong.
Thus, only statement b is correct.

Therefore, the correct answer is option (A).

Note: At present, about 30 well characterized sulphur allotropes are known. Allotropes are arrangements of atoms that differ for the same element (different structural forms). Isotopes are atoms that have a different nucleus.