For a tetrahedral complex [MCl₄]^2-, the spin-only magnetic moment is 3.83 B.M. The element M is:

1. Co

2. Cu

3. Mn

4. Fe

Among the following, the species that is both tetrahedral and diamagnetic is

1.  ${\left[{\mathrm{NiCl}}_4\right]}^{2-}$

2.  ${\left[\mathrm{Ni}{\left(\mathrm{CN}\right)}_4\right]}^{2-}$

3.  $\left[\mathrm{Ni}{\left(\mathrm{CO}\right)}_4\right]$

4.  ${\left[\mathrm{Ni}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{2+}$

The number of ions produced in water by the dissolution of the complex $\left[\mathrm{CO}{\left({\mathrm{NH}}_3\right)}_4{\mathrm{Cl}}_2\right]\mathrm{CI}$ having the empirical formula is

1.  1

2.  2

3.  4

4.  3

In aqueous solution, ${\left[\mathrm{Co}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{2+}$ (X) reacts with molecular oxygen in the presence of excess liquor $N{H}_3$ to give a new complex Y. The number of unpaired electrons in X and Y are, respectively

1.  3,1

2.  3,0

3.  3,3

4.  7,0 

The number of geometrical isomers of $\left[{\mathrm{CrCI}}_2\left(\mathrm{en}\right){\left({\mathrm{NH}}_3\right)}_2\right]$, where en = ethylenediamine, is

1.  2

2.  3

3.  4

4.  1

The energies of ${\mathrm{d}}_{\mathrm{xy}} \mathrm{and} {{\mathrm{d}}_{\mathrm{z}}}^2$ orbitals in octahedral and tetrahedral transition metal complexes are such that

1.  $\mathrm{E}\left({\mathrm{d}}_{\mathrm{xy}}\right) > \mathrm{E}\left({\mathrm{d}}_{{\mathrm{z}}^2}\right)$ in both tetrahedral and octahedral complexes

2.  $\mathrm{E}\left({\mathrm{d}}_{\mathrm{xy}}\right) < \mathrm{E}\left({\mathrm{d}}_{{\mathrm{z}}^2}\right)$ in both tetrahedral and octahedral complexes

3.  $\mathrm{E}\left({\mathrm{d}}_{\mathrm{xy}}\right) > \mathrm{E}\left({\mathrm{d}}_{{\mathrm{z}}^2}\right)$ in tetrahedral but $\mathrm{E}\left({\mathrm{d}}_{\mathrm{xy}}\right) < \mathrm{E}\left({\mathrm{d}}_{{\mathrm{z}}^2}\right)$ in octahedral complexes

4.   $\mathrm{E}\left({\mathrm{d}}_{\mathrm{xy}}\right) < \mathrm{E}\left({\mathrm{d}}_{{\mathrm{z}}^2}\right)$  in tetrahedral but $\mathrm{E}\left({\mathrm{d}}_{\mathrm{xy}}\right) > \mathrm{E}\left({\mathrm{d}}_{{\mathrm{z}}^2}\right)$ in octahedral complexes   

The geometry and the number of the unpaired electron(s) of ${\left[{\mathrm{MnBr}}_4\right]}^{2-}$, respectively, are

1.  Tetrahedral and 1

2.  Square planar and 1

3.   Tetrahedral and 5

4.  Square planar and 5 

Among the following complexes, the one that can exhibit optical activity is

1.  ${\left[{\mathrm{CoCl}}_6\right]}^{3-}$

2.  ${\left[\mathrm{Co}\left(\mathrm{en}\right){\mathrm{CI}}_4\right]}^{-}$

3.  $\mathrm{cis}-{\left[\mathrm{Co}{\left(\mathrm{en}\right)}_2{\mathrm{Cl}}_2\right]}^{+}$

4.  trans-${\left[\mathrm{Co}{\left(\mathrm{en}\right)}_2{\mathrm{Cl}}_2\right]}^{+}$

2.335 g of compound X (empirical formal ${\mathrm{CoH}}_{12}{\mathrm{N}}_4{\mathrm{Cl}}_3$) upon treatment with excess ${\mathrm{AgNO}}_3$ solution produces 1.435 g of a white precipitate. The primary and secondary valences of cobalt in compound X, respectively are

[Given Atomic mass: Co = 59, Cl = 35.5, Ag = 108]

1.  3, 6

2.  3,  4

3.  2,  4

4.  4, 3

 $$\begin{gathered} \mathrm{Among} \left(\mathrm{i}\right) {\left[\mathrm{Cr}{\left(\mathrm{en}\right)}_3\right]}^{3+}, \left(\mathrm{ii}\right) \mathrm{trans}-{\left[\mathrm{Cr}{\left(\mathrm{en}\right)}_2{\mathrm{Cl}}_2\right]}^{+}, \\ \left(\mathrm{iii}\right) \mathrm{cis}-{\left[\mathrm{Cr}{\left(\mathrm{en}\right)}_2{\mathrm{Cl}}_2\right]}^{+}, \left(\mathrm{iv}\right) {\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_4\mathrm{Cl}\right]}^{+}, \mathrm{the} \mathrm{optically} \mathrm{active} \\ \mathrm{complexes} \mathrm{are} \end{gathered}$$

1.  (i) and (ii)

2.  (i) and (iii)

3.  (ii) and (iii)

4.  (ii) and (iv)