Question

Select the correct options according to Hund's rule and Pauli exclusion principle.

• A. Both I and II
• B. Both II and III
• C. Both I and III
• D. Both III and IV

Hint:

Hund's rule maximizes total spin for a given electronic configuration, while Pauli's principle ensures each electron has a unique quantum state.

Answer 1

The Correct Option is D

Step 1: Understanding the Concept:
Hund's rule states that electrons fill degenerate orbitals singly with parallel spins before pairing. Pauli's exclusion principle states that no two electrons in an atom can have the same set of four quantum numbers.

Step 2: Detailed Explanation:
• Configuration I: Violates Pauli's principle (two electrons with same spin in same orbital is not allowed, but this shows opposite spins, so it might be correct if it were not for the pairing in the second p orbital without singly filling the first, which violates Hund's rule). • Configuration II: Violates Hund's rule (electrons pair in the first p orbital without occupying the other orbitals singly). • Configuration III: Follows Hund's rule (all p orbitals are singly occupied with parallel spins). • Configuration IV: Follows Pauli's principle (electrons in the same orbital have opposite spins) and is the correct ground state configuration. Configurations III and IV are correct according to the rules.

Step 3: Final Answer:
The correct options are III and IV, which corresponds to option (D).