Question

The possible value of $l$ and $m$ for the last electron in the $C{l}^{-}$ ion are:

• A. $1$ and $2$
• B. $2$ and $+1$
• C. $3$ and $-1$
• D. $1$ and $-1$

Answer 1

Answer: (D)

$C{l}_{17}^{-}:[Ne]3s^{2}3p^6$
Last electron enters $3p$ orbital.
$\therefore l=1$ and $m=1,0,-1$