Question

What is the oxidation number of oxygen in superoxides?

Answer 1

Oxidation number: Oxidation number denotes the oxidation state of an element in a compound ascertained according to a set of rules formulated on the basis that electron pair in a covalent bond belongs entirely to a more electronegative element.

Calculating the oxidation number of oxygen in superoxide

Example: Potassium oxide(KO₂)

The oxidation state of Potassium(K) = +1

Consider the oxidation state of Oxygen(O) = x

Now,

$$\begin{gathered} +1+\left(-2\mathrm{x}\right)=0 \\ \mathrm{x}=\frac{1}{2} \end{gathered}$$

Hence, the oxidation number of oxygen in superoxide is $-\frac{1}{2}$.