Question

$Ni{\left(CO\right)}_4$ and ${\left[Ni{\left(N{H}_3\right)}_4\right]}^{2+}$ do not differ in :

• A. magnetic moment
• B. oxidation number of Ni
• C. geometry
• D. EAN (Effective Atomic Number)

Answer 1

The correct option is A magnetic moment

$Ni{\left(CO\right)}_4$, $Ni,d^{10},EAN=28+8=36,s{p}^3$ hybridization and tetrahedral geometry.
Here, Ni has zero unpaired electron and hence, zero magnetic moment.
${\left[Ni{\left(N{H}_3\right)}_4\right]}^{2+}$, $N{i}^{+2},d^8,EAN=26+8=34,ds{p}^2$ hybridization and square planar geometry.
Here, Ni has zero unpaired electron and hence, zero magnetic moment.