The number of unpaired electrons in the complex ion $[CoF_6]^{3-}$ is (Atomic number of $Co = 27$).

Identify the correct decreasing order of wavelength of light absorbed for the following complex ions:
$I. [Co(H_2O)_6]^{3+}$
$II. [Co(CN)_6]^{3-}$
$III. [CoI_6]^{3-}$
$IV. [Co(en)_3]^{3+}$

Which of the following is a high spin complex? (Where $\Delta_0$ = splitting energy of octahedral complex,$P.E.$ = Pairing energy)

Match the following complexes in List-$I$ with their electronic configurations in List-$II$.

List-$I$ (Complex)	List-$II$ (Electronic configuration of metal/ion)
$A. [Co(NH_3)_6]^{3+}$	$I. t_{2g}^5 e_g^0$
$B. [CoF_6]^{3-}$	$II. t_{2g}^6 e_g^0$
$C. [Ni(CO)_4]$	$III. t_{2g}^4 e_g^2$
$D. [Fe(CN)_6]^{3-}$	$IV. t^4 e^6$

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:
$(i)$ $[CoF_{6}]^{3-}, [Co(H_{2}O)_{6}]^{2+}, [Co(CN)_{6}]^{3-}$
$(ii)$ $[FeF_{6}]^{3-}, [Fe(H_{2}O)_{6}]^{2+}, [Fe(CN)_{6}]^{4-}$

Arrange the following ligands in the order of increasing field strength.

$I$. $H_2O$	$II$. $CO$
$III$. $NH_3$	$IV$. $I^{-}$
$V$. $F^{-}$