(N/A) $(i)$ Potassium diaquadioxalatochromate$(III)$ trihydrate.
Oxidation state of $Cr = +3$.
Electronic configuration: $3d^3 (t_{2g}^3)$.
Coordination number $= 6$.
Shape: Octahedral. Stereochemistry: Shows cis-trans isomerism.
Magnetic moment,$\mu = \sqrt{3(3+2)} = \sqrt{15} \approx 3.87 \ BM$.
$(ii)$ Pentaamminechloridocobalt$(III)$ chloride.
Oxidation state of $Co = +3$.
Electronic configuration: $3d^6 (t_{2g}^6)$.
Coordination number $= 6$.
Shape: Octahedral. Stereochemistry: Shows geometrical isomerism.
Magnetic moment,$\mu = 0 \ BM$ (diamagnetic).
$(iii)$ Trichloridotripyridinechromium$(III)$.
Oxidation state of $Cr = +3$.
Electronic configuration: $3d^3 (t_{2g}^3)$.
Coordination number $= 6$.
Shape: Octahedral. Stereochemistry: Shows facial $(fac)$ and meridional $(mer)$ isomerism.
Magnetic moment,$\mu = \sqrt{3(3+2)} = \sqrt{15} \approx 3.87 \ BM$.
$(iv)$ Caesium tetrachloroferrate$(III)$.
Oxidation state of $Fe = +3$.
Electronic configuration: $3d^5 (e_g^2 t_{2g}^3)$.
Coordination number $= 4$.
Shape: Tetrahedral. Stereochemistry: Optically inactive.
Magnetic moment,$\mu = \sqrt{5(5+2)} = \sqrt{35} \approx 5.92 \ BM$.
$(v)$ Potassium hexacyanomanganate$(II)$.
Oxidation state of $Mn = +2$.
Electronic configuration: $3d^5 (t_{2g}^5)$.
Coordination number $= 6$.
Shape: Octahedral. Stereochemistry: Optically inactive.
Magnetic moment,$\mu = \sqrt{1(1+2)} = \sqrt{3} \approx 1.73 \ BM$.