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

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

1.  2

2.  3

3.  4

4.  1

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

The total number of geometrical isomers possible for an octahedral complex of this type $\left[{\mathrm{MA}}_2{\mathrm{B}}_2{\mathrm{C}}_2\right]$ is 

(M = transition metal; A, B and C are monodentate ligands)

1.  3

2.  4

3.  5

4.  6

The metal carbonyl which is paramagnetic is

1.  Ni ${\left(\mathrm{CO}\right)}_4$

2.  V ${\left(\mathrm{CO}\right)}_6$

3.  Cr ${\left(\mathrm{CO}\right)}_6$

4.  Fe ${\left(\mathrm{CO}\right)}_5$

The complex having zero crystal field stabilization energy is

1.  ${\left[\mathrm{Mn}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$

2.  ${\left[\mathrm{Fe}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$

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

4.  ${\left[\mathrm{Co}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{3+}$

IUPAC name of complex ion ${\left[{\mathrm{CrCl}}_2{\left(\mathrm{ox}\right)}_2\right]}^{3-}$ is

1.  Dichlorodioxalatochromium (lll)

2.  Dioxalatodichloromate (lll)

3.  Dichlorodioxalatochromate (lll)

4.  Bisoxalaedichlorochromate (lll)

Which of the following complexes formed by ${\mathrm{Cu}}^{2+}$ ions is most stable?

1.  ${\mathrm{Cu}}^{2+}+4{\mathrm{NH}}_3 \rightleftharpoons {\left[\mathrm{Cu}{\left({\mathrm{NH}}_3\right)}_4\right]}^{2+}, \log \mathrm{K}=11.6$

2.  ${\mathrm{Cu}}^{2+} + 4\mathrm{CN}– \rightleftharpoons [\mathrm{Cu}{\left(\mathrm{CN}\right)}_4{]}^{2-} , \mathrm{logK} = 27.3$

3.  ${\mathrm{Cu}}^{2+} + 2\mathrm{en} \rightleftharpoons [\mathrm{Cu}{\left(\mathrm{en}\right)}_2{]}^{2+} , \mathrm{logK} = 15.4$

4.  ${\mathrm{Cu}}^{2+} + 4{\mathrm{H}}_2\mathrm{O} \rightleftharpoons [\mathrm{Cu}{\left({\mathrm{H}}_2\mathrm{O}\right)}_4{]}^{2+} , \mathrm{logK} = 8.9$