Question

What is the coordination number of copper in ${\left[\mathrm{Cu}{\left({\mathrm{NH}}_3\right)}_4\right]}^{2+}$.

Answer 1

Coordination number:

• The number of (ligand) donor atoms which are directly bonded to the central metal by a coordination bond in a coordination complex is known as the coordination number.
• The atoms, ions, or molecules that are bonded to the central atom are called ligands.

${\left[\mathrm{Cu}{\left({\mathrm{NH}}_3\right)}_4\right]}^{2+}$:

• Copper is the central metal to which $4$ molecules of ammine are bonded by a coordination bond.
• Thus, the coordination number of copper in the above coordination complex is $4$