Q.

Match List I with List II.                                                 [2024]

  List I   List II
A. K2[Ni(CN)4] I. sp3
B. [Ni(CO)4] II. sp3d2
C. [Co(NH3)6]Cl3 III. dsp2
D. Na3[CoF6] IV. d2sp3

 

Choose the correct answer from the options given below:

1 A-I, B-III, C-II, D-IV   
2 A-III, B-II, C-IV, D-I   
3 A-III, B-I, C-II, D-IV   
4 A-III, B-I, C-IV, D-II  

Ans.

(4)

A.   [Ni(CN)4]2-

     Oxidation number of Ni = +2

CN- is strong field ligand hence causes pairing of 3d8 electrons, then causes dsp2 hybridization using 3d, 4s and 4p orbitals.

B.   [Ni(CO)4] :

     oxidation number of Ni = 0

CO is a strong field ligand. It shifts 4s electrons to 3d orbital to give 3d10 configuration.

4s orbital becomes vacant. Ni then undergoes sp3 hybridization and lone pairs from CO are accommodated in sp3 orbitals.

C.  [Co(NH3)6]3+

     Oxidation number of Co = +3

NH3 is a strong field ligand. It pairs up d electrons. After pairing d electrons, two 3d orbitals are vacant. Co3+ undergoes d2sp3 hybridisation by using two 3d orbitals. Six e- pairs from six NH3 are accommodated in these six d2sp3 orbitals.

D.   [CoF6]3-

Oxidation number of Co = +3

F- is a weak field ligand. It cannot pair up d electrons. Thus 4d orbitals are used for sp3d2 hybridization. Six e- pairs from six F- are accommodated in these six sp3d2 orbitals.