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)

square planar

$N{H}_3$ has more field strength. So it forms low spin complexes. So, the metal ion becomes diamagnetic. Here as $N{H}_3$ is a low spin complex which allows electrons of $Cu$ to pair up.

$4\left(N{H}_3\right)$ molecules has $8$ electrons. So, they require $4$ sub orbitals - $1d,1s,2p$. So its hybridization becomes $ds{p}^2$. Its co-ordination number $=4$

Co-ordination number and hybridization decides the shape with $4$ co-ordination number and $ds{p}^2$ hybridization, it has a square planar structure.

Option B is correct.