Question

What is the oxidation number of Pt in $K\left[PtN{H}_{3}C{l}_5\right]$?

• A. 0
• B. 1
• C. 2
• D. 4

Answer 1

The correct option is D 4

Let X be the oxidation number of $Pt$ in $K\left[PtN{H}_{3}C{l}_5\right]$. The oxidation numbers of $K,N{H}_3$ and $Cl$ are $+1$, $0$ and $-1$ respectively.
$1+X+0+5(-1)=0$

$1+X-5=0$

$X=+4$

Hence, the oxidation number of $Pt$ in $K\left[PtN{H}_{3}C{l}_5\right]$ is $+4$.

Option $D$ is the correct answer.