Question

Nitrogen form N2, but phosphorous form P2, it's at a time convert in P4, reason is :

Answer 1

Due to larger atomic size P is unable to form pi bonds and so it is tetra-atomic in which each P atom is linked with 3 other P atoms by 3 sigma bond. But, due to smaller atomic size N forms 1 sigma and 2 pi bonds i.e. triple bonds with other N atom and exists as diatomic molecule.