The hybridization of the complex $\left[{\mathrm{CrCl}}_2\right({\mathrm{NO}}_2{)}_2({\mathrm{NH}}_3{)}_2{]}^{-}$ is:

1. ${\mathrm{sp}}^3{\mathrm{d}}^2$                       

2. ${\mathrm{d}}^2{\mathrm{sp}}^3$

3. ${\mathrm{sp}}^3\mathrm{d}$                         

4. Cannot be predicted 

The following complexes are given :

(1) $\mathrm{trans}-\left[\mathrm{Co}\right({\mathrm{NH}}_3{)}_4{\mathrm{Cl}}_2{]}^{+}$

(2) $\mathrm{cis}-\left[\mathrm{Co}\right({\mathrm{NH}}_3{)}_2(\mathrm{en}{)}_2{]}^{3+}$

(3) $\mathrm{trans}-\left[\mathrm{Co}\right({\mathrm{NH}}_3{)}_2(\mathrm{en}{)}_2{]}^{3+}$

(4) ${\mathrm{NiCl}}_4^{2-}$

(5) ${\mathrm{TiF}}_6^{2-}$

(6) ${\mathrm{CoF}}_6^{3-}$

Choose the correct code:

(a) (1),(2) are optically active, (3) is optically inactive

(b) (2) is optically active ; (1), (3) are optically inactive

(c) (4), (5) are coloured and (6) is colourless

(d) (4) is coloured and (5),(6) are colourless

Which of the following isomerism, exhibited by $\left[{\mathrm{CrCl}}_2\right(\mathrm{OH}{)}_2\left({\mathrm{NH}}_3{)}_2\right]$?

(1)Ionization     

(2) Geometrical

(3) Hydrate       

(4) Linkage

Which of the following is true about the complex $\left[{\mathrm{PtCl}}_2\right({\mathrm{H}}_2\mathrm{O}\left)\right({\mathrm{NH}}_3\left)\right]$ ?

(1) It exhibits geometrical isomerism

(2) It is a paramagnetic complex

(3) Its geometry is a tetrahedron 

(4) Platinum is ${\mathrm{sp}}^3$ hybridized 

Aqueous solution of Ni²⁺ contains [Ni(H₂O)₆]²⁺ and its magnetic moment is 2.83 BM. When ammonia is added in it, the magnetic moment of solution:

1. Will remain the same.

2. Will increase from 2.83 BM.

3. Will decrease from 2.83 BM.

4. Cannot be predicted theoretically.

[Co(NH₃)₄(NO₂)₂]Cl can show:

Copper sulphate dissolves in excess of KCN to give :

(1) CuCN

(2) [Cu(CN)₄]^3-

(3) [Cu(CN₄]^2-

(4) Cu(CN)₂

The d-electron configurations of Cr²⁺, Mn²⁺, Fe²⁺ and Ni²⁺ are 3d⁴, 3d⁵, 3d⁶ and 3d⁸ respectively. Which one of the following aqua complexes will exhibit the minimum paramagnetic behaviour?

(1)[Mn(H₂O)₆]²⁺(2) [Fe(H₂O)₆]²⁺

(3) [Ni(H₂O)₆]²⁺(4) [Cr(H₂O)₆]²⁺

(At. no. Cr=24, Mn=25, Fe=26, Ni=28)

Which of the following complex ions is not expected to absorb visible light ?

1. [Ni(CN)₄]^2-

2. [Cr(NH₃)₆]³⁺

3. [Fe(H₂O)₆]²⁺

4. [Ni(H₂O)₆]²⁺

The complexes [CO(NH₃)₆][Cr(CN)₆] and [Cr(NH₃)₆][Co(CN)₆] are examples of: