Question

Which allotrogic form of phosphorus has discrete tetrahedral P${}_4$ Molecule? How is Phosphine prepared in the laboratory? Give the equation.

Answer 1

Allotropes of phosphorous having discrete $P_4$ molecule are-

White phosphorous and Yellow phosphorous.

(Refer to Image)

Preparation of $P{H}_3$(phosphine)

$\underset{calciumphosphide}{C{a}_3{P}_2}+6H_{2}O⟶2P{H}_3+3Ca(OH{)}_2$

By reacting Calcium phosphide with water we get phosphine. Also, by heating phosphorous acid $P{H}_3$ is obtained.