Question

Write a short note on the anomalous behavior of Nitrogen.

Answer 1

Nitrogen:

• Being the fifth most abundant element in the universe, Nitrogen(${\mathrm{N}}_2$) comprises about 78% of the atmosphere.
• It is the first element in Group 15 of the periodic table.

Reasons for the anomalous behavior of Nitrogen:

• Due to the small size of Nitrogen, it exhibits high ionization enthalpy, high electronegativity, and no d-orbitals.
• Nitrogen exists as a diatomic molecule as ${\mathrm{N}}_2$ comprising of a triple bond whereas all the other elements of Group 15 exist as tetra-atomic molecules comprising a single bond.
• Exhibition of a wide range of oxidation states from $-3$ to $+5$ by Nitrogen while the other elements exhibit only a limited number of oxidation states.
• The absence of d-orbitals in Nitrogen prohibits it from participating in the formation of coordination compounds.
• The small size of Nitrogen enables it in the formation of $p\pi -p\pi$ multiple bonds which is not possible for the other Group 15 elements due to their large and diffused orbital size, hence they form $p\pi -d\pi$ multiple bonds.