The total number of geometrical isomers possible for an octahedral complex of $\left[{\mathrm{MA}}_2{\mathrm{B}}_2{\mathrm{C}}_2\right]$ are:
(M = transition metal; A, B and C are monodentate ligands)

1.	3	2.	4
3.	5	4.	6

The IUPAC name of [Co(ONO)(NH₃)₅]Cl₂ is: 

1.  Pentamminenitrocobalt(II)chloride

2.  Pentamminenitrsoocobalt(III)chloride  

3. Pentaaminenitrito-O-cobalt(III)chloride.  

4. Pentammineoxo-nitrocobalt(III)chloride

The metal carbonyl which is paramagnetic is:

1. NO₃^- acts as a monodentate ligand.
2. The Ce atom has a coordination number of 12.
3. The shape of the complex ion is an icosahedron.
4. The solution is used as an oxidizing agent.

Which one of the following reactions is correct?

1.  $\left[\mathrm{Fe}\right(\mathrm{CO}{)}_5]+2\mathrm{NO}\to \left[\mathrm{Fe}\right(\mathrm{CO}{)}_2\left(\mathrm{NO}{)}_2\right]+3\mathrm{CO}$

2.  $\left[\mathrm{Fe}\right(\mathrm{CO}{)}_5]+2\mathrm{NO}\to \left[\mathrm{Fe}\right(\mathrm{CO}{)}_3\left(\mathrm{NO}{)}_2\right]+2\mathrm{CO}$

3.  $\left[\mathrm{Fe}\right(\mathrm{CO}{)}_5]+3\mathrm{NO}\to \left[\mathrm{Fe}\right(\mathrm{CO}{)}_2\left(\mathrm{NO}{)}_3\right]+3\mathrm{CO}$

4. $\left[\mathrm{Fe}\right(\mathrm{CO}{)}_5]+3\mathrm{NO}\to \left[\mathrm{Fe}\right(\mathrm{CO}{)}_3\left(\mathrm{NO}{)}_3\right]+2\mathrm{CO}$

How many isomers are possible for complex [Co(Ox)₂Cl₂]^3-?

1.  1

2.  3

3.  2

4.  4

Which metal ion is present in Vitamin- B₁₂?

1. Zinc

2. Calcium

3. Iron

4. Cobalt

Hybridization and geometry of ${\left[\mathrm{Ni}{\left(\mathrm{CN}\right)}_4\right]}^{2-}$ are

1.  $s{p}^{2}d$ and tetrahedral

2.  $s{p}^3$ and square planar

3.  $s{p}^3$ and tetrahedral

4.  $ds{p}^2$ and square planar

Among the following complexes, the one that can exist
as facial(fac) and meridional(mer) isomer is: