Question

What are the coordination numbers of cobalt (III), platinum (II), and platinum (VV) in complexes?

Short answer

Cobalt (III) - coordination number: 0

Platinum (II) - coordination number: 4

Platinum (IV) - coordination number: 6

Step-by-step solution

Definition of Coordination Compound

A coordination complex consists of a central atom or ion, which is sometimes metallic and is named the coordination centre, and a surrounding array of bound molecules or ions, that are successively called ligands or complexing agents.

Solve the given statements

The coordination number is that the number of ligands directly attached to central metal ion in an exceedingly complex. These ligands are often ions, atoms or molecules. the foremost common coordination number is 6, but it's also not rare to work out 2 and 4 as coordination numbers.

Cobalt(III) - coordination number: 6; example: ${\left[Co{\left(N{H}_3\right)}_6\right]}^{3+}$

Platinum(II) - coordination number: 4; example: $\left[Pt{\left(N{H}_3\right)}_4\right]C{l}_2$

Platinum(IV) - coordination number: 0; example:$\left[Pt{\left(N{H}_3\right)}_6\right]C{l}_4$