The geometry and magnetic behaviour of the complex [Ni(CO)₄] respectively are:

1. Square planar and diamagnetic.

2. Tetrahedral and diamagnetic.

3. Square planar and paramagnetic.

4. Tetrahedral and paramagnetic.

Number of possible isomers for the complex [Co(en)₂Cl₂]Cl will be:
(en=ethylenediamine) 

The IUPAC name for complex ion, [Fe(CN)₆]^3- is:

A paramagnetic ion among the following, forms an outer orbital complex is:

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

Which among the following is a diamagnetic complex?

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 complex ion among the following that cannot absorb visible light is:

1. [Ni(CN)₄]^2-

2. [Cr(NH₃)₆]³⁺

3. [Fe(H₂O)₆]²⁺

4. [Ni(H₂O)₆]²⁺

The existence of two different coloured complexes with the composition of [Co(NH₃)₄Cl₂]⁺  is due to:

Which among the following complexes can exhibit isomerism?

The crystal field stabilization energies (CFSE) of high spin and low spin $d^6$ metal complexes in terms of ${∆}_0$, respectively are: 

1.  -0.4 and -2.4

2.  -2.4 and -0.4

3.  -0.4 and 0.0

4.  -2.4 and 0.0