Chemistry - Carbonyl compounds Question with Solution | TestHub

Apart from [Ni(CO)₄], all other options have wrong hybridizations. Nickel has the configuration of [Ar]3d84s2. Now,CO is a strong field ligand, so it will pair the electrons to give [Ar]3d104s0. Since inner d orbitals are not available, 4s and 4p orbitals will be used to give sp3 hybridized orbitals. So, the geometry will be tetrahedral

Complex        Hybridisation

$\left[\mathrm{\text{N}}\mathrm{\text{i}}{\left(\mathrm{\text{C}}\mathrm{\text{O}}\right)}_4\right]$$\text{s}{\text{p}}^3$

${\left[\mathrm{\text{N}}\mathrm{\text{i}}{\left(\mathrm{\text{C}}\mathrm{\text{O}}\right)}_4\right]}^{2-}$$\text{d}\text{s}{\text{p}}^2$

${\left[{\mathrm{\text{C}}\mathrm{\text{o}}\mathrm{\text{F}}}_6\right]}^{3-}$sp³d²

${\left[\mathrm{\text{F}}\mathrm{\text{e}}{\left(\mathrm{\text{C}}\mathrm{\text{N}}\right)}_6\right]}^{3-}$${\text{d}}^2\text{s}{\text{p}}^3$