Question

The paramagnetic species among the following is:
$N{a}^{+},Z{n}^{2+},C{u}^{+},F{e}^{3+}$

• A. $N{a}^{+}$
• B. $Z{n}^{2+}$
• C. $C{u}^{+}$
• D. $F{e}^{3+}$

Answer 1

The correct option is D $F{e}^{3+}$

Paramagnetic species have at least one unpaired electron.
$N{a}^{+}:1s^{2}2s^{2}2p^6\text{all electrons are paired}\left(11\right)Z{n}^{2+}:1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}\text{all electrons are paired}\left(30\right)C{u}^{+}:1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}\text{all electrons are paired}\left(29\right)F{e}^{3+}:1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^5\text{have unpaired electrons}\left(26\right)$