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

1.	Electrons in the 3d orbitals remain unpaired in ${\left[\mathrm{Ni}{\left(\mathrm{CN}\right)}_4\right]}^{2-}$
2.	Electrons in the 3d orbitals remain unpaired in [Cr(NH3)6]3+
3.	Electrons in the 3p orbitals remain unpaired in [Cr(NH3)6]3+
4.	Electrons in the 3p orbitals remain unpaired in ${\left[\mathrm{Ni}{\left(\mathrm{CN}\right)}_4\right]}^{2-}$

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

The correct order for the wavelengths of absorption in the visible region for the following is:

$$



\(\left[\mathrm{Ni}\left(\mathrm{NO}_2\right)_6\right]^{4-},\left[\mathrm{Ni}\left(\mathrm{NH}_3\right)_6\right]^{2+},\left[\mathrm{Ni}\left(\mathrm{H}_2 \mathrm{O}\right)_6\right]^{2+}\)
1. $[\mathrm{Ni}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6{]}^{2+}$ < $[\mathrm{Ni}{\left({\mathrm{NH}}_3\right)}_6{]}^{2+}$ < $[\mathrm{Ni}{\left({\mathrm{NO}}_2\right)}_6{]}^{4-}$

2. $[\mathrm{Ni}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6{]}^{2+}$ > $[\mathrm{Ni}{\left({\mathrm{NH}}_3\right)}_6{]}^{2+}$ > $[\mathrm{Ni}{\left({\mathrm{NO}}_2\right)}_6{]}^{4-}$

3. $[\mathrm{Ni}{\left({\mathrm{NH}}_3\right)}_6{]}^{2+}$ > $[\mathrm{Ni}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6{]}^{2+}$ > $[\mathrm{Ni}{\left({\mathrm{NO}}_2\right)}_6{]}^{4-}$

4.  $[\mathrm{Ni}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6{]}^{2+}$ > ${\left[\mathrm{Ni}{\left({\mathrm{NO}}_2\right)}_6\right]}^{4-}$ > [Ni(NH₃)₆]²⁺

The number of unpaired electrons in the following complexes respectively are-

${\mathrm{K}}_4\left[\mathrm{Mn}{\left(\mathrm{CN}\right)}_6\right], \mathrm{Fe}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6{]}^{2+}, {\mathrm{K}}_2\left[{\mathrm{MnCl}}_4\right]$

1. 1, 4, 5

2. 2, 4, 5

3. 0, 3, 4

4. 2, 3, 4

The correct statements among the above are -

1. a, b

2. a, c

3. b, c

4. a, b, c 

Match the following.

1. i=d, ii=c, iii=b, iv=a

2. i=c, ii=d, iii=b, iv=a

3. i=c, ii=d, iii=a, iv=b

4. i=a, ii=c, iii=b, iv=d

The correct representation of tetrahydroxidozincate (II) is:
1. \([Zn(OH)_4]^{2-}\)
2. \([Zn(OH)_4]^{-}\)
3. \([Zn(OH)_4]^{3-}\)
4. \([Zn(OH)_4]\)