If the nitrogen atom had electronic configuration `1s^7` it would have energy lower than that of the normal ground state configuration `1s^2 2s^2 2p^3` because the electrons would be closer to the nucleus. Yet `1s^7` is not observed. It violates

Options

A. Heisenberg's uncertainty principle
B. Hund's rule
C. Pauli exclusion principle
D. Bohr postulate of stationary orbits

Answer

C

Explanation

Not more than two electrons can be present in same atomic orbital. This is Paulis exclusion principle.