Question

While writing the following electronic configuration of Fe atom, which rules have been violated?

I. Aufbau principle II. Hund’s rule III. Pauli’s exclusion principle

• A. I, II
• B. II, III
• C. I, III
• D. I, II, III

Answer 1

The correct option is B II, III

II, III
As two electrons in one orbital can not have the same spin. In degenerate orbitals pairing of $e^{-}$ is not allowed until all the degenerate orbitals contain atleast one $e^{-}$ with same spin.