Question

If the nitrogen atom had electronic configuration ${1s}^7$. This configuration has lower energy than that of the normal ground state configuration ${1s}^2{2s}^2{2p}^3$ because the electrons would be closer to the nucleus but ${1s}^7$ is not observed because it violates

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

Answer 1

The correct option is C Pauli exclusion principle

Pauli's Exclusion Principle:

No two electrons in the same atom can have the same values for all the four quantum numbers.

Two electrons in a given orbital have the same values of n, l and m. Electrons in the same orbital differ in their spin quantum number and they spin in opposite directions.

The consequence of Pauli's Exclusion Principle:

An orbital can not accommodate more than two electrons.

Answer: Pauli's Exclusion Principle as explained above.