Chemistry

Question Analysis
This question evaluates the student's understanding of electron configurations and the application of the Aufbau principle, Pauli exclusion principle, and Hund’s rule.

Key Concept Explanation
Electron configuration describes the distribution of electrons in atomic orbitals.
The Aufbau principle states that electrons fill the lowest-energy orbitals first.
The Pauli exclusion principle limits each orbital to two electrons with opposite spins. Hund’s rule requires electrons in degenerate orbitals to occupy separate orbitals with parallel spins before pairing.

Step-by-step Solution
1. Identify the atomic number of chlorine (Cl), which is 17.
2. Start filling the orbitals in order of increasing energy: 1s, 2s, 2p, 3s, 3p.
3. Fill the 1s orbital with 2 electrons: 1s².
4. Fill the 2s orbital with 2 electrons: 2s².
5. Fill the 2p sublevel wit...