The statements that are incorrect about the nickel(II) complex of dimethylglyoxime are :

A. It is red in colour.

B. It has a high solubility in water at $\mathrm{pH}=9$.

C. The Ni ion has two unpaired d-electrons.

D. The $\mathrm{N}-\mathrm{Ni}-\mathrm{N}$ bond angle is almost close to $90^{\circ}$.

E. The complex contains four five-membered metallacycles (metal containing rings).

Choose the correct answer from the options given below :

Given below are two statements :

Statement I : $\left[\mathrm{CoBr}_4\right]^{2-}$ ion will absorb light of lower energy than $\left[\mathrm{CoCl}_4\right]^{2-}$ ion.

Statement II : In $\left[\mathrm{CoI}_4\right]^{2-}$ ion, the energy separation between the two set of d-orbitals is more than $\left[\mathrm{CoCl}_4\right]^{2-}$ ion.

In the light of the above statements, choose the correct answer from the options given below :

$\left[\mathrm{Ni}\left(\mathrm{PPh}_3\right)_2 \mathrm{Cl}_2\right]$ is a paramagnetic complex. Identify the INCORRECT statements about this complex.

A. The complex exhibits geometrical isomerism.

B. The complex is white in colour.

C. The calculated spin-only magnetic moment of the complex is 2.84 BM .

D. The calculated CFSE (Crystal Field Stabilization Energy) of Ni in this complex is $-0.8 \Delta_{\mathrm{o}}$.

E. The geometrical arrangement of ligands in this complex is similar to that in $\mathrm{Ni}(\mathrm{CO})_4$.

Choose the correct answer from the options given below :

Consider the transition metal ions $\mathrm{Mn}^{3+}, \mathrm{Cr}^{3+}, \mathrm{Fe}^{3+}$ and $\mathrm{Co}^{3+}$ and all form low spin octahedral complexes. The correct decreasing order of unpaired electrons in their respective d-orbitals of the complexes is