6.1.3 Redox Terminology

A redox reaction contains both oxidation and reduction. The oxidised species loses electrons and the reduced species gains electrons.

Use “oxidation” and “reduction” for the changes, then identify the oxidising agent and reducing agent from what each species does.

In Fe²⁺ + Ce⁴⁺ → Fe³⁺ + Ce³⁺, Fe²⁺ is oxidised and acts as the reducing agent; Ce⁴⁺ is reduced and acts as the oxidising agent.

The oxidising agent is itself reduced, while the reducing agent is itself oxidised. Do not assign the labels from the words alone.