The metal d-orbitals that are directly facing the ligands in
Question:

The metal d-orbitals that are directly facing the ligands in $\mathrm{K}_{3}\left[\mathrm{Co}(\mathrm{CN})_{6}\right]$ are :

1. $\mathrm{d}_{\mathrm{xz}}, \mathrm{d}_{\mathrm{yz}}$ and $\mathrm{d}_{\mathrm{z}^{2}}$

2. $d_{x y}, d_{x z}$ and $d_{y z}$

3. $\mathrm{d}_{x y}$ and $\mathrm{d}_{x^{2}-y^{2}}$

4. $\mathrm{d}_{\mathrm{x}^{2}-\mathrm{y}^{2}}$ and $\mathrm{d}_{\mathrm{z}^{2}}$

Correct Option: , 4

Solution:

$\mathrm{K}_{3}\left[\mathrm{Co}(\mathrm{CN})_{6}\right]$

$\mathrm{Co}^{+3} \rightarrow[\mathrm{Ar}]_{18} 3 \mathrm{~d}^{6}$