Question

The shape of ${\left[Cu{\left(N{H}_3\right)}_4\right]}^{2+}$ is

• A. tetrahedral
• B. square planar
• C. pyramidal
• D. octahedral.

Answer 1

Answer: (B)

Oxidation state of $Cu$ in ${\left[Cu{\left(N{H}_3\right)}_4\right]}^{2+}=+2$
$C{u}^{2+}\left(Z=29\right)\to 3d^9$

One electron is shifted from 3d to 4p-orbital. Thus, ${\left[Cu{\left(N{H}_3\right)}_4\right]}^{2+}$ is $ds{p}^2$ hybridised and has square planar geometry.