Correct set of four quantum numbers for the unpaired electron of chloride atom is — Atomic Structure Chemistry Question

💡 Solution & Explanation

Chlorine (Cl) has atomic number 17. Its electronic configuration is $[Ne] 3s^2 3p^5$. The unpaired electron is in the 3p subshell. For a 3p electron, $n=3$ and $l=1$. The magnetic quantum number $m$ can be -1, 0, or +1. The spin $s$ can be +1/2 or -1/2. Option (b) $n=3, l=1, m=0, s=+1/2$ is a valid set. Therefore, correct answer is B.