JEE Main 2022 — Coordination Compounds Question with Solution

Complexes in which central atom has unpaired electrons is said to be paramagnetic in nature and where unpaired electrons are not present are diamagnetic in nature.

${\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_6\right]}^{3-}$,   ${\mathrm{Fe}}^{+3}$  $\left(3{\mathrm{d}}^5\right) \to {{\mathrm{t}}_{2\mathrm{g}}^{}}^{2,2} {{\mathrm{e}}_{\mathrm{g}}}^1$, paramagnetic (one unpaired electron)

${\left[\mathrm{Fe}{\left(\mathrm{CN}\right)}_6\right]}^{4-}, {\mathrm{Fe}}^{+2} \left(3{\mathrm{d}}^6\right)\to {{\mathrm{t}}_{2\mathrm{g}}}^6{{\mathrm{e}}_{\mathrm{g}}}^0$ ,diamagnetic 

${\left[\mathrm{Ti}{\left(\mathrm{CN}\right)}_6\right]}^{3-}, {\mathrm{Ti}}^{+3}\left(3{\mathrm{d}}^1\right)\to {{\mathrm{t}}_{2\mathrm{g}}}^1$ , Paramagnetic ($1$ unpaired electron)

${\left[\mathrm{Ni}{\left(\mathrm{CN}\right)}_4\right]}^{2-}, {\mathrm{Ni}}^{+2}\left(3d^8\right)\to$ Diamagnetic

${\left[\mathrm{Co}{\left(\mathrm{CN}\right)}_6\right]}^{3-}, {\mathrm{Co}}^{+3}\left(3{\mathrm{d}}^6\right)\to {{\mathrm{t}}_{2\mathrm{g}}}^6, \mathrm{diamagnetic}$