What is an example of a disproportionation reaction?

Feb 27, 2017

The disproportionation of hydrogen peroxide to give oxygen and water would be a good example.

Explanation:

$\text{The formal oxidation number}$ of oxygen in $\text{hydrogen peroxide}$ is ${O}^{- I}$. ${H}_{2} {O}_{2}$ disproportionates to oxygen and water under acidic conditions:

$\text{Oxidation:}$

${H}_{2} {O}_{2} \rightarrow 2 {H}^{+} + {O}_{2} + 2 {e}^{-}$

$\text{Reduction:}$

${H}_{2} {O}_{2} + 2 {H}^{+} + 2 {e}^{-} \rightarrow 2 {H}_{2} O \left(l\right)$

$\text{Overall:}$

$2 {H}_{2} {O}_{2} \left(l\right) + \rightarrow 2 {H}_{2} O \left(l\right) + {O}_{2} \left(g\right)$

OR

${H}_{2} {O}_{2} \left(l\right) + \rightarrow {H}_{2} O \left(l\right) + \frac{1}{2} {O}_{2} \left(g\right)$

Univalent oxygen in hydrogen peroxide is reduced to water, and oxidized to dioxygen gas.