Complexes containing halide ligands are generally .....

Write down the number of $3d$ electrons in each of the following ions:
$Ti^{2+}, V^{2+}, Cr^{3+}, Mn^{2+}, Fe^{2+}, Fe^{3+}, Co^{2+}, Ni^{2+}$ and $Cu^{2+}$
Indicate how you would expect the five $3d$ orbitals to be occupied for these hydrated ions (octahedral).

How many of the following ligands are stronger than $H_2O$? $S^{2-}$,$Br^{-}$,$C_2O_4^{2-}$,$CN^{-}$,$en$,$NH_3$,$CO$,$OH^{-}$

Three complexes,$[CoCl(NH_3)_5]^{2+} (I)$,$[Co(NH_3)_5H_2O]^{3+} (II)$ and $[Co(NH_3)_6]^{3+} (III)$ absorb light in the visible region. The correct order of the wavelength of light absorbed by them is

Which of the following complexes will absorb the maximum wavelength of light?

In which of the following coordination entities the magnitude of $\Delta_o$ ($CFSE$ in octahedral field) will be maximum? (Atomic Number of $Co = 27$)