Question:
The total number of unpaired electrons present in the complex $\mathrm{K}_{3}\left[\mathrm{Cr}\right.$ (oxalate) $\left._{3}\right]$ is
Solution:
$\mathrm{K}_{3}\left[\mathrm{Cr}(\text { oxalate })_{3}\right]$
Chromium is in $+3$ oxidation state.
Number of unpaired electrons in $\mathrm{Cr}^{+3}$ will be 3 .