Give reason for the statement `[Ni(CN)_(4)]^(2-)` is diamagnetic while `[NiCl_(4)]^(2-)` is paramagnetic in nature .

Options

A. In `[NiCl_(4)]^(2-)` no unpaired electrons are present while in `[Ni(CN)_(4)]^(2-)` two unpaired electrons are present
B. In `[Ni(CN)_(4)]^(2-)` , no unpaired electrons are present while in `[NiCl_(4)]^(2-)` two unpaired electrons are present .
C. `[NiCl_(4)]^(2-)` shows `dsp^(2)` hybridisation hence it is paramagnetic .
D. `[Ni(CN)_(4)]^(2-)` shows `sp^(3)` hybridisation hence it is diamagnetic .

Answer

B

Explanation

In `[Ni(CN)_(4)]^(2-)` there is no unpaired electrons because `CN^(-)` is a strong field ligand . Therefore it is diamagnetic in nature .

In `[NiCl_(4)]^(2-)` , there are two unpaired electrons because `Cl^(-)` is a weak field ligand . Therefore , it is paramagnetic in nature .