Question

Among $[Ni(CO{)}_4],[Ni(CN{)}_4{]}^{2-},[NiC{l}_4{]}^{2-}$ species, the hybridisation states of the $Ni$ atom are, respectively (At. no. of $Ni=28$)

• A. $s{p}^3,ds{p}^{2}ds{p}^2$
• B. $s{p}^3,ds{p}^2,s{p}^3$
• C. $s{p}^3,s{p}^3,ds{p}^2$
• D. $ds{p}^2,s{p}^3,s{p}^3$

Answer 1

Answer: (B)

Outermost electronic configuration of $\left[Ni(CO{)}_4\right]$ complex is $3d^8,4s^2$ and $CO$ is a strong ligand thus electrons get paired up and shows $s{p}^3$ hybridisation.
Outermost electronic configuration of ${\left[Ni(CN{)}_4\right]}^{2-}$ complex is $3d^8$ and $CN$ is a strong ligand thus electrons get paired up but one d orbital is empty and shows dsp ${}^2$ hybridisation.
Outermost electronic configuration of ${\left[Ni(Cl{)}_4\right]}^{2-}$ complex is $3d^8,4s^2$ and $Cl$ is a weak ligand thus electrons does not paired up and shows $s{p}^3$ hybridisation.