Which is/are correct for sodium atom, in the ground state? — Atomic Structure Chemistry Question

💡 Solution & Explanation

Na ($1s^2 2s^2 2p^6 3s^1$) has 10 paired electrons (5 pairs) and 1 unpaired electron. Hence, 5 spins are of one orientation and 6 ($5+1$) are of the opposite orientation. Therefore, correct answer is A, B, C.