Question

What will be the geometry and magnetic moment of the complex $[NiC{l}_4{]}^{2-}$ ?

• A. Tetrahedral and $3.87B.M$
• B. Tetrahedral and $2.82B.M$
• C. Square planar and $2.82B.M$
• D. Square planar and $4.89B.M$

Answer 1

Answer: (B)

$N{i}^{2+}\Rightarrow [Ar]3d^8$
In a weak field ligand, pairing does not take place
So, $[NiC{l}_4{]}^{2-}:[Ar]$
Thus, geometry is tetrahedral with two unpaired electrons
Magnetic moment $=\sqrt{n\left(n+2\right)}$
$\sqrt{2\left(4\right)}$
$=2.82B.M.$