The Brainliest Answer!
Because nitrogen has half filled orbitals and is stable....................
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Dinitrogen is rather inert at room temperature because of the highbond enthalpy of N≡N bond.

Phosphorus catches flame because of angularstrain in the P4 molecule where the angles are only 60°. It readilycatches fire in air to give dense white fumes of P₄O₁₀.
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