Multiple choice What is the the number of unpaired electrons in chromic ion Cr3+ (Atomic number: 24)? 6 2 4 3 - Reveal answer Fill a bubble to check yourself D Correct answer Explanation The electronic configuration of chromium is 1s2, 2s2, 2p6, 3s2, 3p6, 3d5, 4s1. Therefore, by the removal of 3 electrons it results in 3 unpaired electrons in the outer shell.