question_answer

The presence of unpaired electron in phosphorous atom is explained by which principle?

A)  Aufbau principle

B)  Faults exclusion principle

C)  Hunds rule

D)  Heisenbergs principle

Correct Answer: C

Solution :

The presence of unpaired electron in phosphorus atom is explained by Hunds rule, which states that Pairing of electrons in\[d\]and\[f-\]orbitals cant occur until each orbital of a given subshell contains one electron or is singly occupied                 \[_{15}P:1{{s}^{2}},\,\,2{{s}^{2}},\,\,2{{p}^{6}},\,\,3{{s}^{2}},\,\,3p_{x}^{1},\,\,3p_{y}^{1},\,\,3p_{z}^{1}\]