Using crystal field theory,draw energy level diagrams,write the electronic configuration of the central metal atom/ion,and determine the magnetic moment value for the following:
$(i)$ $[CoF_{6}]^{3-}, [Co(H_{2}O)_{6}]^{2+}, [Co(CN)_{6}]^{3-}$
$(ii)$ $[FeF_{6}]^{3-}, [Fe(H_{2}O)_{6}]^{2+}, [Fe(CN)_{6}]^{4-}$

(N/A) The magnetic moment $\mu$ is calculated using the formula $\mu = \sqrt{n(n+2)} \ BM$,where $n$ is the number of unpaired electrons.
$(i)$ $[CoF_{6}]^{3-}$: $Co^{3+}$ $(3d^{6})$,weak field ligand,$t_{2g}^{4} e_{g}^{2}$,$n=4$,$\mu = \sqrt{4(4+2)} = 4.90 \ BM$.
$[Co(H_{2}O)_{6}]^{2+}$: $Co^{2+}$ $(3d^{7})$,weak field ligand,$t_{2g}^{5} e_{g}^{2}$,$n=3$,$\mu = \sqrt{3(3+2)} = 3.87 \ BM$.
$[Co(CN)_{6}]^{3-}$: $Co^{3+}$ $(3d^{6})$,strong field ligand,$t_{2g}^{6} e_{g}^{0}$,$n=0$,$\mu = 0 \ BM$.
$(ii)$ $[FeF_{6}]^{3-}$: $Fe^{3+}$ $(3d^{5})$,weak field ligand,$t_{2g}^{3} e_{g}^{2}$,$n=5$,$\mu = \sqrt{5(5+2)} = 5.92 \ BM$.
$[Fe(H_{2}O)_{6}]^{2+}$: $Fe^{2+}$ $(3d^{6})$,weak field ligand,$t_{2g}^{4} e_{g}^{2}$,$n=4$,$\mu = \sqrt{4(4+2)} = 4.90 \ BM$.
$[Fe(CN)_{6}]^{4-}$: $Fe^{2+}$ $(3d^{6})$,strong field ligand,$t_{2g}^{6} e_{g}^{0}$,$n=0$,$\mu = 0 \ BM$.