The complexes given below show:

Sulphide ions react with sodium nitroprusside in a basic medium giving a coloured solution. In the reaction,the oxidation state of iron:

Write down the $IUPAC$ name for each of the following complexes and indicate the oxidation state,electronic configuration,and coordination number. Also,give the stereochemistry and magnetic moment of the complex:
$(i)$ $K[Cr(H_2O)_2(C_2O_4)_2] \cdot 3H_2O$
$(ii)$ $[Co(NH_3)_5Cl]Cl_2$
$(iii)$ $CrCl_3(py)_3$
$(iv)$ $Cs[FeCl_4]$
$(v)$ $K_4[Mn(CN)_6]$

Which of the following compounds is brown coloured?

Which of the following statements is not correct?

Among the statements $(a)-(d)$,the incorrect ones are:
$(a)$ Octahedral $Co(III)$ complexes with strong field ligands have very high magnetic moments.
$(b)$ When $\Delta_{0} < P$,the $d-$electron configuration of $Co(III)$ in an octahedral complex is $t_{2g}^{4} e_{g}^{2}$.
$(c)$ Wavelength of light absorbed by $[Co(en)_{3}]^{3+}$ is lower than that of $[CoF_{6}]^{3-}$.
$(d)$ If the $\Delta_{0}$ for an octahedral complex of $Co(III)$ is $18,000 \ cm^{-1}$,the $\Delta_{t}$ for its tetrahedral complex with the same ligand will be $16,000 \ cm^{-1}$.