Question: Identify the element for which electronic configuration in $+3$ oxidation state is $[\mathrm{Ar}] 3 \mathrm{~d}^{5}:$
$\mathrm{Ru}$
$\mathrm{Mn}$
$\mathrm{Co}$
$\mathrm{Fe}$
Correct Option: , 4
Solution:
$\mathrm{Fe}^{3+}[\mathrm{Ar}] 3 \mathrm{~d}^{5}$
