${\mathrm{FeSO}}_4$ solution mixed with ${\left({\mathrm{NH}}_4\right)}_2{\mathrm{SO}}_4$ solution in 1:1 molar ratio gives the test of Fe²⁺ ion but ${\text{CuSO}}_4$ solution mixed with aqueous ammonia in 1:4 molar ratio does not give the test of Cu²⁺ ion because:

1.	The former is an example of a basic compound, while the latter is an amphoteric compound
2.	The former is an example of an amphoteric compound, while the latter is a basic compound
3.	The former is an example of a double salt, while the latter is a coordination compound
4.	The former is an example of a coordination compound, while the latter is a double salt

The oxidation number and coordination number of Co in $\left[\mathrm{Co}\right({\mathrm{H}}_2\mathrm{O}\left)\right(\mathrm{CN}){\left(\mathrm{en}\right)}_2{]}^{2+}$respectively are:    

1. 3, 6

2. 3, 2

3. 2, 2

4. 1, 3

Total number of optical isomers [Pt(NH₃)(Br)(Cl)(py)] can show:

1. 3

2. 2

3. 1

4. 0

The difference between a weak field ligand and a strong field ligand is:

The crystal field splitting energy is:

[Cr(NH₃)₆]³⁺ is paramagnetic ,while ${\left[\mathrm{Ni}{\left(\mathrm{CN}\right)}_4\right]}^{2-}$ is diamagnetic because:

A solution of [Ni(H₂O)₆]²⁺ is green, but a solution of [Ni(CN)₄]^2– is colorless because:

[Fe(CN)₆]^4– and [Fe(H₂O)₆]²⁺ are of different colors in dilute solutions because :

The nature of bonding in metal carbonyls is -

The greater value of the stability constant of complex salt indicates:

1. The greater proportion of products.

2. The greater proportion of reactants

3. Lesser concentration of catalyst at equilibrium

4. All of the above