Question

Sulfur molecule is:
A. diatomic
B. triatomic
C. tetraatomic
D. octa-atomic.

Answer 1

Hint : Sulfur molecules have different atomicity. But only one is stable. Catenation is the major reason for this property.

Complete step by step solution :
Sulfur is a chemical element with atomic number 16. It is abundant, multivalent and non-metallic. Sulfur lies in the oxygen group. But an oxygen molecule is diatomic, i.e., its atomicity is two. Sulfur behaves differently. Sulfur prefers to form single bonds rather than double bonds. It is bigger in size and the van der Waals forces are also strong. Moreover it exists in a solid structure unlike oxygen which exists in a gaseous state at room temperature. ${{\text{S}}_8}$ is the most stable allotrope of sulfur at room temperature. Electronic configuration of sulfur is $1{{\text{s}}^2}2{{\text{s}}^2}2{{\text{p}}^6}3{{\text{s}}^2}3{{\text{p}}^4}$which is similar to oxygen. Octa sulfur exists in cyclic structure. Elemental sulfur is a soft and odorless yellow powder.
Sulfur exists as ${{\text{S}}_8}$because of catenation. Catenation is the covalent bonding of elements to form a chain or ring.
Elemental sulfur is used as a precursor to other chemicals. Sulfur with methane gives carbon disulfide, which is used in preparation of cellophane and rayon. Major use of sulfur is vulcanization of rubber. It is also used in pesticides.

Additional information:
Sulfur is a source of metabolic energy for many bacteria. Sulfur reacts with all elements like gold, iridium, platinum, tellurium and noble gases. Sulfur occurs as sulfide or sulfate minerals in nature.

Note : The point group of ${{\text{S}}_8}$is ${{\text{D}}_{4{\text{d}}}}$and its dipole moment is $0{\text{D}}$. It has a very high boiling point and melting point. It sublimes easily, i.e., it changes directly to gaseous state very easily. The structure of ${{\text{S}}_8}$ring is virtually unchanged by this phase change.