When an element undergoes both oxidation and reduction in the same reaction, it is called a disproportionation reaction.

Here's a breakdown:

* Oxidation: Loss of electrons

* Reduction: Gain of electrons

* Disproportionation: A single element is both oxidized and reduced within the same reaction.

Example:

The reaction of chlorine with water:

Cl₂(g) + H₂O(l) → HCl(aq) + HOCl(aq)

In this reaction, chlorine (Cl₂) is both oxidized to hypochlorous acid (HOCl) and reduced to hydrochloric acid (HCl).

Let me know if you would like more examples or a deeper explanation!