State Hund's rule of maxium multiplicity. How is it used in electronic distribution in nitrogen atom `(Z=7)`?

Answer

Hund's rule: No electron pairing takes place in the orbitals in a sub-shell untill each orbital is occupied by one electron with parallel spin. Exactly half filled and fully filled orbitals make the atoms more stable, i.e., `p^(3), p^(6), d^(5), d^(10), f^(7)` and `f^(14)` configuration are most stable.
`N=1s^(2)2s^(2)2p^(3)`
`(##RES_PHY_CHM_V01_XI_C02_E01_030_S01##)`