AQA · GCSE · 8462
Chemistry — Keywords & Key Terms — Definitions Glossary (2026)
AQA GCSE Chemistry (8462) — Specification (2026)
Topic-by-topic keywords, key terms and definitions for precise exam language—separate from our revision checklists (topic coverage) and formula sheets (equations).
Keywords & Key Terms — definitions
Examiner-style keywords and definitions organised by syllabus topic. Terms are tagged Essential (start here), Core (typical exam standard), and Advanced for harder distinctions — tick each row when you can recall it. Your progress is saved in this browser for this list.
AQA GCSE Chemistry (8462)
AQA GCSE Chemistry (8462)
AQA GCSE Chemistry (8462) — Specification (2026)
Topics follow AQA GCSE Chemistry headings (atomic structure & periodic table; bonding/structure; quantitative chemistry; chemical changes; energy changes; rate & extent; organic; chemical analysis; chemistry of the atmosphere; using resources).
Mark schemes: AQA mark schemes credit correct chemical terminology (e.g., ‘electrostatic attraction’, ‘oxidation is loss of electrons’). Use particle-level explanations and include state symbols, charges, and balanced equations where required.
Active recall: 0 / 51 terms ticked
| Recalled | Topic | Level | Keyword | Definition |
|---|---|---|---|---|
| Atomic structure & the periodic table | Essential | Atom | The smallest part of an element that retains its chemical properties. | |
| Atomic structure & the periodic table | Core | Relative atomic mass (Ar) | The weighted mean mass of an atom compared with 1/12 of the mass of carbon-12. | |
| Atomic structure & the periodic table | Core | Ion | A charged particle formed when an atom (or group of atoms) gains or loses electrons. | |
| Atomic structure & the periodic table | Core | Isotope | Atoms of the same element with different numbers of neutrons. | |
| Atomic structure & the periodic table | Advanced | Periodic table | A table of elements arranged by atomic number, showing repeating patterns in properties. | |
| Bonding, structure & properties | Essential | Ionic bond | Electrostatic attraction between oppositely charged ions formed by electron transfer. | |
| Bonding, structure & properties | Core | Covalent bond | A shared pair of electrons between atoms. | |
| Bonding, structure & properties | Core | Metallic bonding | Attraction between positive metal ions and delocalised electrons. | |
| Bonding, structure & properties | Advanced | Giant covalent structure | A large network of covalent bonds (e.g., diamond, SiO2) with high melting point. | |
| Quantitative chemistry | Essential | Relative formula mass (Mr) | Sum of relative atomic masses of all atoms in a formula unit. | |
| Quantitative chemistry | Core | Mole | Amount of substance containing 6.02 × 10²³ particles (Avogadro constant). | |
| Quantitative chemistry | Core | Concentration | Amount of solute per unit volume of solution, often in mol/dm³. | |
| Quantitative chemistry | Advanced | Limiting reactant | The reactant that is used up first and limits the amount of product formed. | |
| Chemical changes | Essential | Acid | A substance that produces H⁺ (hydrogen) ions in aqueous solution. | |
| Chemical changes | Core | Base | A substance that neutralises an acid; accepts H⁺ ions. | |
| Chemical changes | Core | Neutralisation | Reaction between an acid and a base to form a salt and water. | |
| Chemical changes | Advanced | Electrolysis | Decomposition of an ionic compound by passing an electric current through it (molten or in solution). | |
| Chemical changes | Core | Redox | Reactions involving oxidation and reduction, often via electron transfer. | |
| Chemical changes | Core | Oxidation | Loss of electrons (or gain of oxygen) during a reaction. | |
| Chemical changes | Core | Reduction | Gain of electrons (or loss of oxygen) during a reaction. | |
| Chemical changes | Advanced | Reactivity series | A list ranking metals by how readily they form positive ions (react). | |
| Chemical changes | Advanced | Displacement reaction | A more reactive element replaces a less reactive element in a compound. | |
| Energy changes | Essential | Exothermic reaction | A reaction that transfers energy to the surroundings, causing a temperature rise. | |
| Energy changes | Essential | Endothermic reaction | A reaction that takes in energy from the surroundings, causing a temperature fall. | |
| Energy changes | Core | Activation energy | Minimum energy needed for particles to react successfully. | |
| Energy changes | Core | Catalyst | A substance that increases reaction rate without being used up, by lowering activation energy. | |
| Energy changes | Advanced | Energy profile diagram | A diagram showing how energy changes during a reaction (reactants → products). | |
| Rate & extent of chemical change | Core | Rate of reaction | Change in quantity of reactant used (or product formed) per unit time. | |
| Rate & extent of chemical change | Core | Collision theory | Reactions occur when particles collide with enough energy and correct orientation. | |
| Rate & extent of chemical change | Core | Concentration (rate) | Higher concentration increases collision frequency, increasing rate. | |
| Rate & extent of chemical change | Core | Surface area | A larger surface area increases collisions per second, increasing rate. | |
| Rate & extent of chemical change | Advanced | Equilibrium | In a closed system, forward and reverse reactions occur at equal rates. | |
| Rate & extent of chemical change | Advanced | Le Chatelier’s principle | A system at equilibrium shifts to oppose a change in conditions. | |
| Organic chemistry | Essential | Hydrocarbon | A compound containing only hydrogen and carbon. | |
| Organic chemistry | Core | Alkane | A saturated hydrocarbon with single C–C bonds only. | |
| Organic chemistry | Core | Alkene | An unsaturated hydrocarbon containing at least one C=C double bond. | |
| Organic chemistry | Core | Cracking | Breaking long-chain hydrocarbons into shorter alkanes and alkenes. | |
| Organic chemistry | Advanced | Polymerisation | Joining many small monomer molecules into a long-chain polymer. | |
| Organic chemistry | Advanced | Fermentation | Anaerobic breakdown of sugars by yeast to produce ethanol and carbon dioxide. | |
| Chemical analysis | Core | Purity | A measure of how much of a sample is the desired substance (not contaminants). | |
| Chemical analysis | Core | Chromatography | A technique to separate mixtures by different solubilities/attractions. | |
| Chemical analysis | Core | Filtration | Separating an insoluble solid from a liquid using filter paper. | |
| Chemical analysis | Core | Crystallisation | Forming crystals from a solution to obtain a soluble solid. | |
| Chemical analysis | Advanced | Titration | A method to find concentration by reacting measured volumes to an end point. | |
| Chemical analysis | Advanced | Indicator | A substance that changes colour over a narrow pH range to show an end point. | |
| Chemistry of the atmosphere & resources | Core | Greenhouse gas | A gas that absorbs infrared radiation, contributing to the greenhouse effect. | |
| Chemistry of the atmosphere & resources | Core | Carbon footprint | Total greenhouse gas emissions caused directly and indirectly by an activity/product. | |
| Chemistry of the atmosphere & resources | Core | Potable water | Water that is safe to drink. | |
| Chemistry of the atmosphere & resources | Advanced | Life cycle assessment (LCA) | Evaluating environmental impacts from raw materials to disposal. | |
| Chemistry of the atmosphere & resources | Advanced | Finite resource | A resource that will eventually run out if used faster than it is replaced. | |
| Chemistry of the atmosphere & resources | Advanced | Renewable resource | A resource that can be replenished naturally on a human timescale. |
Pair this with our revision checklists, formula sheets hub and past paper finder.
Chemistry (8462) — Keywords & Key Terms FAQ
- What is on this AQA GCSE Chemistry keywords and key terms list?
- It is a topic-organised glossary of important chemistry terms with short, exam-style definitions aligned to AQA GCSE Chemistry (8462) — Specification (2026) (8462). It is designed for “define”, “state”, “outline” and “explain” questions where precise vocabulary earns marks.
- How should I use this Chemistry glossary alongside past papers?
- Tick terms when you can recall them without reading the answer, then check your wording against mark schemes. Pair vocabulary practice with past papers for GCSE Chemistry (8462) so you apply terms in context.
- Is this the same as a revision checklist or a formula sheet?
- No. Revision checklists help you track which syllabus topics you have covered and your confidence—separate pages on Tutopiya. Formula sheets summarise equations and quantitative relationships. This page is only a definitions and key-terms glossary for Chemistry. Quantitative relationships belong on formula sheets; this list emphasises language and concepts.
- Can I download this Chemistry keywords and key terms list for free?
- Yes. After a quick free sign-up you can download a UTF-8 CSV (opens in Excel or Google Sheets) or open a print-friendly page and save as PDF. Browsing the list on the page is free.
- Is this Chemistry list aligned to the 8462 specification?
- Topic groupings and wording follow AQA GCSE Chemistry (8462) — Specification (2026) for AQA GCSE. Always confirm final learning objectives and any regional options in your official specification and recent examiner reports for your exam session.
- Why focus on definitions instead of full notes?
- Mark schemes reward correct technical terms and clear links between ideas. A compact glossary lets you drill the exact language examiners expect for Chemistry at GCSE, separate from longer notes or topic trackers.