The order of energy absorbed, which is responsible for the color of the following complexes, is:
$A: [Ni(H_{2}O)_{2}(en)_{2}]^{2+}$
$B: [Ni(H_{2}O)_{4}(en)]^{2+}$
$C: [Ni(en)_{3}]^{2+}$

The correct statements among $I$ to $III$ are:
$I$. Valence bond theory cannot explain the color exhibited by transition metal complexes.
$II$. Valence bond theory can predict quantitatively the magnetic properties of transition metal complexes.
$III$. Valence bond theory cannot distinguish ligands as weak and strong field ones.

In which one of the following complexes does the metal ion have a $t_{2g}^3 e_g^2$ configuration?

Crystal field splitting energy $(CFSE)$ for $[CoCl_6]^{4-}$ is $18000 \ cm^{-1}$. The crystal field splitting energy $(CFSE)$ for $[CoCl_4]^{2-}$ will be (in $cm^{-1}$)

Complexes with $CN^-$ ligands are generally...

For the crystal field splitting in octahedral complexes,