Question

Why does nitrogen exist as n2 and phosphorus as p4?

Answer 1

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

Answer 2

Hey!

It is because - N2 contains a pi bond between two N atoms. But P4 does not. It lacks the pi bond and it is because unstable pi tend to overlap among two P atoms.

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DisPater