Multiple choice What is the correct electron configuration for Mg? 1s2 2s2 2p6 3s2 1s2 2s2 1s2 2s2 3p2 1s2 2s2 2p6 Reveal answer Fill a bubble to check yourself A Correct answer Explanation Magnesium (Mg) has 12 electrons. The configuration 1s2 2s2 2p6 3s2 accounts for all 12 electrons.