Question

Find the difference in the number of electrons in $t_{2g}$ and $e_g$ set of orbitals of the complex $N{a}_3\left[Co{F}_6\right]$:

Answer 1

The oxidation state of $Co$ in $N{a}_3\left[Co{F}_6\right]$ is $+3$. It has $6$ electrons in $3d$ orbital out of which $4$ are present in $t_{2g}$ level and $2$ are present in $e_g$ level since it is a high spin complex.
Hence, the difference in the number of electrons in $t_{2g}$ and $e_g$ set of orbitals of $N{a}_3\left[Co{F}_6\right]$ is $4-2=2$