Chapter summary
Redox Chemistry, at a glance
Track electrons through reactions, electrolysis and electricity-producing cells.
O-Level 5086 / 5088 (2026) / SEC G3 K326 / K328 (2027)
Quick revision
Revisit the essentials, then return to an explanation when you need it.
| Term | Definition to write |
|---|---|
| Oxidation | Gain of oxygen, loss of hydrogen, loss of electrons, or an increase in oxidation state. |
| Reduction | Loss of oxygen, gain of hydrogen, gain of electrons, or a decrease in oxidation state. |
| Oxidising agent | A substance that oxidises another substance; it is itself reduced (it gains electrons). |
| Reducing agent | A substance that reduces another substance; it is itself oxidised (it loses electrons). |
| Term | Meaning |
|---|---|
| Oxidation | Electron loss; oxidation state rises |
| Reduction | Electron gain; oxidation state falls |
| Oxidising agent | Accepts electrons and is reduced |
| Reducing agent | Supplies electrons and is oxidised |
Quick recall
Define oxidation in terms of oxygen, electrons and oxidation state.