Nitrogen atom can bond with another nitrogen atom by strong pπ–pπ overlap resulting in N≡N. The triple bond in N₂ has high bond strength resulting in high bond dissociation energy. Phosphorous do not show this property of pπ–pπ overlap. Hence, nitrogen is less reactive than phosphorous.

The p-orbitals which interact to form two π bonds in N₂ molecule are shown by joining them with a curve line.