Question

In the reaction: $M+O_2\to M{O}_2$ (superoxide), the metal $M$ is:

• A. $Li$
• B. $Na$
• C. $K$
• D. $Ba$

Answer 1

The correct option is C $K$

The formation of oxides, peroxides and superoxides depends on the size of the alkali metal. An atom with a larger size produces superoxide. $Li$ forms oxide, $Na$ forms peroxide, whereas potassium with larger size forms superoxide.