Question

Oxidation number of carbon in $SC{N}^{-}$ ion is

• A. $+2$
• B. $-2$
• C. $+4$
• D. $-4$

Answer 1

The correct option is C $+4$

In thiocyanate ion ($SC{N}^{-}$), carbon atom is attached to $N$ via single bond and $S$ via triple bond. The oxidation numbers of S and N are $-2$ and $-3$ respectively.
Let, $x$ be the oxidation number of C. The total charge on ion is $-1$. Hence, $-2+x+(-3)=-1$ or, $x=+4$.
The structure of $SC{N}^{-}$ is given below: