Chemistry

Question Analysis
This question assesses the student's ability to write the full electron configuration of an element following the Aufbau principle.

Key Concept Explanation
The Aufbau principle states that electrons fill the lowest-energy orbitals first.
The order of filling is 1s → 2s → 2p → 3s → 3p → 4s → 3d → 4p → 5s → 4d → 5p → 6s.

Step-by-step Solution
1. Determine the total number of electrons in a magnesium atom: 12.
2. Fill the orbitals in order: 1s (2 electrons) → 2s (2 electrons) → 2p (6 electrons) → 3s (2 electrons).
3. There...