Question

What is the difference between peroxide and superoxide?

Answer 1

Hint : Oxides are compounds containing one or more oxygen atoms. Both peroxide and superoxide are oxides that contain oxygen atoms. But there are some differences between these oxides. Oxidation state of peroxide and superoxide is different.

Complete Step By Step Answer:
Peroxides are composed of an oxygen-oxygen single bond. Where the $ O - O $ bond length is $ {1.49^0}A $ The electronic charge on peroxide is $ - 2 $ . Examples of peroxide compounds include $ N{a_2}{O_2} $ , $ {K_2}{O_2} $ and $ {H_2}{O_2} $
Now, let’s talk about superoxide.
Superoxides are compounds containing the anion $ {O_2}^ - $ , The electronic charge is $ - 1 $ , The $ O - O $ bond length in superoxide is $ {1.33^0}A $ . Examples of superoxide compounds include $ Na{O_2} $ , $ K{O_2} $ and $ Rb{O_2} $
The major difference between a peroxide and a superoxide is the oxidation state of oxygen. In superoxide, the oxidation state of oxygen is $ - 0.5 $ . While in case of peroxide, the oxidation state of oxygen is $ - 1 $
Important point to keep in mind is that metals such as alkali, earth alkali and non-metals can form peroxide compounds. But only alkali metals can form superoxide compounds.

Additional Information:
If superoxide is dissolved in water, it will rapidly undergo a disproportionation reaction forming $ {O_2} $ and $ O{H^ - } $ ions. Peroxides can be easily found in nature and in biological systems. Some plants use peroxide as a signalling chemical. Certain cells in our body use peroxides to catalyse the chemical reactions. Peroxide is also a very useful reagent in organic chemistry.

Note :
Apart from oxidation state there are many other differences as well between these oxides. Hydrogen peroxide is the simplest peroxide. Also, superoxide is composed of highly reactive oxygen atoms.