How many unpaired electrons are present in ground state of chromium (Z = 24)? — Atomic Structure Chemistry Question

💡 Solution & Explanation

The neutral chromium atom (Z = 24) has an anomalous ground-state configuration of [Ar] 3d^5 4s^1 instead of [Ar] 3d^4 4s^2, because of the extra stability associated with a symmetric, half-filled d-subshell. In the 3d^5 subshell, there are 5 unpaired electrons, and in the 4s^1 subshell, there is 1 unpaired electron. The total number of unpaired electrons in the ground state of chromium is therefore 5 + 1 = 6.