The correct statement, among the following, is:

1.	[Co(CN)6]3- has no unpaired electrons and will be in a low-spin configuration.
2.	[Co(CN)6]3- has four unpaired electrons and will be in a low-spin configuration.
3.	[Co(CN)6]3- has four unpaired electrons and will be In a high-spin configuration.
4.	[Co(CN)6]3- has no unpaired electrons and will be in a high-spin configuration.

Among the following complexes the one which shows zero crystal field stabilization energy (CFSE) is:

1. $\left[Ni\right(H_{2}O{)}_6{]}^{3+}$

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

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

4. $\left[Co\right(H_{2}O{)}_6{]}^{3+}$

An ion that has magnetic moment 2.83 BM is:
(Atomic Number: Ti=22, Cr=24, Mn=25, Ni=28)

1. $T{i}^{3+}$

2. $N{i}^{2+}$

3. $C{r}^{3+}$

4. $M{n}^{2+}$

An anticancer agent among the following is:

1. $\mathrm{mer}-\left[\mathrm{Co}\right({\mathrm{NH}}_3{)}_3\mathrm{Cl}]$

2. c$\mathrm{is}-\left[{\mathrm{PtCl}}_2\right({\mathrm{NH}}_3{)}_2]$

3. c$\mathrm{is}-{\mathrm{K}}_2[\mathrm{Pt}$ ${\mathrm{Cl}}_2{\mathrm{Br}}_2]$

4. ${\mathrm{NH}}_2{\mathrm{CoCl}}_4$

Which one of the following is an outer orbital complex and exhibits paramagnetic behavior?

1. $\left[Ni\right(N{H}_3{)}_6{]}^{2+}$

2. $\left[Zn\right(N{H}_3{)}_6{]}^{2+}$

3. $\left[Cr\right(N{H}_3{)}_6{]}^{3+}$

4. $\left[Co\right(N{H}_3{)}_6{]}^{3+}$

The d-electron configurations of Cr²⁺, Mn²⁺, Fe²⁺ and Co²⁺ are d⁴, d⁵, d⁶, and d⁷ respectively. Minimum paramagnetic behavior is shown by:
(At. No C = 24, Mn = 25, Fe = 26, Co = 27)

1. [Fe(H₂O)₆]²⁺

2. [Co(H₂O)₆]²⁺

3. [Cr(H₂O)₆]²⁺

4. [Mn(H₂O)₆]²⁺

Of the following complex ions, which is diamagnetic in nature?

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

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

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

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

The complexes [Co(NH₃)₆][Cr(CN)₆] and [Cr(NH₃)₆][Co(CN)₆] show:

1. Ionisation isomerism

2. Co-ordination isomerism

3. Geometrical isomerism

4. Linkage isomerism