Arrange the following Cobalt complexes in the order of increasing Crystal Field Stabilization Energy (CFSE) value.
Complexes : $\left[\underset{\mathrm{A}}{\mathrm{CoF}_{6}}\right]^{3-},\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+},\left[\underset{\mathrm{B}}{\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}}\right]^{3+}$ and $\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{3+}$
Choose the correct option :
Correct Option: , 2
(i) CFSE $\propto$ charge or oxidation no. of central metal ion.
(ii) $\mathrm{CFSE} \propto$ strength of ligand
$\mathrm{en}>\mathrm{NH}_{3}>\mathrm{H}_{2} \mathrm{O}>\mathrm{F}^{-}$
$\therefore$ order of CFSE
$\left.\left[\mathrm{Co}(\mathrm{en})_{3}\right]^{+3}>\mathrm{Co}\left(\mathrm{NH}_{3}\right)_{6}\right]^{+3}>\left[\mathrm{CoF}_{6}\right]^{-3}>\left[\mathrm{Co}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{+2}$