Question

What is the oxidation state and coordination number of platinum respectively in
\[ \left[\mathrm{Pt(NH_3)_6}\right]^{4+}\,? \]

• A. \(+6\) and \(4\)
• B. \(+4\) and \(4\)
• C. \(+6\) and \(6\)
• D. \(+4\) and \(6\)

Hint:

Neutral ligands like \(\mathrm{NH_3}\) do not affect oxidation state but always count toward coordination number.

Answer 1

The Correct Option is D

Step 1: Determine oxidation state of platinum.
In the complex \(\left[\mathrm{Pt(NH_3)_6}\right]^{4+}\), ammonia is a neutral ligand.
Let the oxidation state of Pt be \(x\). Then:
\[ x + 6(0) = +4 \Rightarrow x = +4 \]
Step 2: Determine coordination number.
The coordination number is equal to the number of ligands directly bonded to the metal ion. Here, six \(\mathrm{NH_3}\) ligands are attached to platinum.
Step 3: Conclusion.
Thus, the oxidation state of platinum is \(+4\) and the coordination number is \(6\).