Question

What is the coordination number of platinum in the complex ion cis-diamminedichloroplatinum(ii)?

Answer 1

Answer: The coordination number of platinum is 4.

Step-by-step explanation:

Coordination number is defined as the number of ligands that are attached to the central metal atom in a complex ion.

The complex given to us is: cis-diamminedichloroplatinum(ii)

The chemical formula for this complex is
`[Pt(NH_3)_2Cl_2]`

In this complex, two ammine atoms are attached to platinum and two chlorine atoms are attached to platinum. This complex is also named as Cisplatin.

The structure of this complex is given in the image attached.

Hence, the coordination number of platinum is 4.

Answer 2

`[Pt(NH_3)_2Cl_2]^(2-)`

Coordination Number is the number of atoms or ions immediately surrounding a central atom in a complex or crystal.
Obviously here the Coordination Number is 4. Pt is the central atom. It is surrounded by NH3 and Cl