Question

Which of the following complex does not possess square planar shape?

• A. $\left[Ni\right(Cl{)}_4{]}^{-2}]$
• B. $\left[Ni\right(CN{)}_4{]}^{-2}]$
• C. $\left[CU\right(NH{)}_3{]}^{+2}]$
• D. $\left[Pt\right(N{H}_3{)}_{2}C{l}_2]$

Answer 1

The correct option is A $\left[Ni\right(Cl{)}_4{]}^{-2}]$

$[NiC{l}_4{]}^{2-}⟶$ Oxidation state of $Ni$ is $x-4=-2\Rightarrow x=+2$

$N{i}^{+2}⟶3d^8$ configuration

as $Cl$ is a weak field ligands thus filling will be

(Refer to Image 1)

as $Cl$ is a weak field ligand thus it will not pair the electron of Nickel. Thus it will use $4s$ & $4p$ orbitals for bonding and form $s{p}^3$ hybrid geometry i.e tetrahedral.

(Refer to Image 2)

Thus $[NiC{l}_4{]}^2$ has tetrahedral geometry and not square planar geometry.