Question

The incorrect statement among the following is 

(a) C₆₀ is an allotropic form of carbon 

(b) O₃ is an allotropic form of oxygen 

(c) S₈ is only allotropic form of sulphur 

(d) red phosphorus is more stable in air than white phosphorus.

Answer 1

The correct option is (c) S₈ is only allotropic form of sulphur.

Explanation:

The different allotropic forms of sulphur arises partly from the extent to which S has polymerised and partly from the crystal strucfures adopted. 

The two common crystalline forms are α-rhombic sulphur and β-monoclinic sulphur. A third modification is y-monoclinic sulphur. All three forms contain puckered S₈ rings with a crown conformation. 

Engel's sulphur (e-sulphur) contains S₆ rings. S₇, S₈, S₁₀, S₁₁, S₁₂, S₁₈ and S₂₀ rings have been made by Schmidt and his group. 

Plastic or y-sulphur contains spiral chains and sometimes S₈ and other rings. 

The other allotropic forms of sulphur are milk of sulphur and colloidal or δ-sulphur.