Geometrical shapes of the complexes formed by the reaction of `Ni^(2+)` with ` H2O , Cl^-`, and `CN^- `, respectively are

Options

A. Octahedral tetrahedral and square planar
B. Tetrahedral,square planar and octahedral
C. Square planar,tetrahedral,octahedral
D. Octahedral,square palnar and octahedral

Answer

b

Explanation

(i) `Ni^(2+) +4CI^(Θ)rarr[NiCI_(4)]^(2-)` (Tetrahderal)
`Ni(Z=28) =3d^(8) 4s^(2), Ni^(2) =3d^(8)`
Since `CI^(Θ)` ion is weak ligand so pairing does not occur, thus `sp^(3)` hybridisation and is tetrahedral
(ii) `Ni^(2+) + 4CN^(o+)rarr[Ni(CN)_(4)]^(2-)` (Square planar) Since `CN^(Θ)` ion is a strong ligand, so pairing occurs, thus `dsp^(2)` hybridisation and is square planar.
(iii) `Ni^(2+) +H_(2)Orarr [Ni(H_(2)O)_(6)]^(2+)` (Octahedral) Since `H_(2)O` is a weak ligand so pairing does not occur thus `sp^(3)d^(2)` (outer complex) hybridisation and is octahedral