The number of bridging carbonyl groups in [Co₂(CO)₈] and [Mn₂(CO)₁₀], respectively are:
1. 2 and 0
2. 2 and 2
3. 2 and 4
4. 0 and 2

Iron carbonyl, $\mathrm{Fe}{\left(\mathrm{CO}\right)}_5$, is classified as:

The  complex ion that does not expected to absorb visible light is:

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

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

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

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

Anticancer agent among the following is:

1.		2.
3.		4.

A metal ion present in vitamin B₁₂ is:

The organometallic compound that is σ and $\mathrm{\pi }$ bonded is:

1. $\left[Fe{({\eta }^5-C_5{H}_5)}_2\right]$

2. $K\left[PtC{l}_3\right({\eta }^2-C_2{H}_4\left)\right]$

3. ${\left[Co{\left(CO\right)}_{5}N{H}_3\right]}^{+2}$

4. $Fe{\left(C{H}_3\right)}_3$

The shape of Fe(CO)₅ is:

Mg is present in: