Question

Find oxidation number of Carbon in $C_3{O}_2$.

Answer 1

$C_3{O}_2\Rightarrow \stackrel{-2}{O}=\stackrel{+2}{\underset{\left(1\right)}{C}}=\stackrel{0}{\underset{\left(2\right)}{C}}=\stackrel{+2}{\underset{\left(3\right)}{C}}=\stackrel{-2}{O}$

Oxidation number of $C_1=+2$

Oxidation number of $C_2=0$

Oxidation number of $C_3=+2$

Average oxidation number of $C=\frac{+2+0+2}{3}=+\frac{4}{3}$