Question

Which of the following ion has the maximum number of unpaired electrons?

• A. Zn${}^{+2}$
• B. Fe${}^{+3}$
• C. Mn${}^{+3}$
• D. Cu${}^{+1}$

Answer 1

The correct option is B Fe${}^{+3}$

Electronic configuration of ions:

$F{e}^{+3}$ - $\left[Ar\right]3d^5$
$M{n}^{+3}$ - $\left[Ar\right]3d^4$
$C{u}^{+}$ - $\left[Ar\right]3d^{10}$
$Z{n}^{+2}$ - $\left[Ar\right]3d^{10}$

$F{e}^{+3}$ has 5 unpaired electrons.