This definitions covers Key Definitions within Oxidation & Reduction for GCSE Chemistry. Revise Oxidation & Reduction in Chemical Changes for GCSE Chemistry with 20 exam-style questions and 20 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 7 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Topic position
Section 7 of 14
Practice
20 questions
Recall
20 flashcards
📖 Key Definitions
Oxidation: The loss of electrons (or gain of oxygen, or loss of hydrogen). Electrons are transferred away from the species being oxidised.
Reduction: The gain of electrons (or loss of oxygen, or gain of hydrogen). Electrons are transferred to the species being reduced.
Redox reaction: A reaction in which both oxidation and reduction occur simultaneously. Electrons are transferred from the reducing agent to the oxidising agent.
Oxidising agent: The substance that causes another substance to be oxidised — it accepts electrons and is itself reduced in the process.
Reducing agent: The substance that causes another substance to be reduced — it donates electrons and is itself oxidised in the process.
OIL RIG: Oxidation Is Loss (of electrons), Reduction Is Gain (of electrons). The single most important mnemonic in GCSE Chemistry redox.