MCQ
Oxidation number of $C$ in $HNC$ is
- ✓$+2$
- B$-3$
- C$+3$
- D$0$
✓
Answer
Correct option: A.
$+2$
a
$H-\stackrel{..}{N}\stackrel{\rightarrow}{=}C$
$H-\stackrel{..}{N}\stackrel{\rightarrow}{=}C$
$+1 \; \stackrel{-1}{-2}\,+2$
direction of co-ordinate bond is from more $EN$ atom to less $EN$ atom. So there is no development of charge due to this co-ordinate bond.
So in $\mathrm{HNC} \Rightarrow$
$\mathrm{O} \cdot \mathrm{N} \text { of } \mathrm{H}=+1$
$\mathrm{O} \cdot \mathrm{N}$ of $\mathrm{N}=-3$
$\mathrm{O} \cdot \mathrm{N}$ of $\mathrm{C}=+2$
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