AQA GCSE CHEMISTRY KEY WORDS QUESTIONS
WITH CORRECT ANSWERS 2026-2027
Accurate - CORRECT ANSWER -
A measurement is considered accurate if it is judged to be close to the true value.
Acid - CORRECT ANSWER -
When dissolved in water, its solution has a pH value less than 7. Acids are proton (H+ ion) donors.
Activation energy - CORRECT ANSWER -The minimum energy needed for a reaction to take place.
Akali metal - CORRECT ANSWER -Elements in Group 1 of the periodic table.
Alkali - CORRECT ANSWER -Its solution has a pH value more than 7.
Alkane - CORRECT ANSWER -
Saturated hydrocarbon with the general formula CnH2n+2, for example, methane, ethane, and propan
e.
Alkene - CORRECT ANSWER -Unsaturated hydrocarbon which contains a carbon-
carbon double bond. Its general formula is CnH2n, for example, ethene, C2H4.
Alloy - CORRECT ANSWER -A mixture of two or more elements, at least one of which is a metal.
Anhydrous - CORRECT ANSWER -Describes a substance that does not contain water.
Anode - CORRECT ANSWER -The positive electrode in electrolysis.
Anomalies - CORRECT ANSWER -
Results that do not match the pattern seen in the other data collected or are well outside the range o
f other repeat readings (outliers).
,Aqueous solution - CORRECT ANSWER -The mixture made by adding a soluble substance to water.
Atmosphere - CORRECT ANSWER -The relatively thin layer of gases that surround planet Earth.
Atom - CORRECT ANSWER -
The smallest part of an element that can still be recognised as that element.
Atom - CORRECT ANSWER -
A measure of the amount of starting materials that end up as useful products.
Atomic number - CORRECT ANSWER -
The number of protons (which equals the number of electrons) in an atom. It is sometimes called the
proton number.
Avagadro constant - CORRECT ANSWER -
The number of atoms, molecules, or ions in a mole of any substance (i.e., 6.02 × 1023 per mol).
Balanced symbol equation - CORRECT ANSWER -
A symbol equation in which there are equal numbers of each type of atom on either side of the equat
ion.
Base - CORRECT ANSWER -
The oxide, hydroxide, or carbonate of a metal that will react with an acid, forming a salt as one of the
products. (If a base dissolves in water it is called an alkali). Bases are proton (H+ ion) acceptors.
Biodegradable - CORRECT ANSWER -Materials that can be broken down by microorganisms.
Biofuel - CORRECT ANSWER -Fuel made from animal or plant products.
Blast furnace - CORRECT ANSWER -
The huge reaction vessels used in industry to extract iron from its ore.
, Bond energy - CORRECT ANSWER -The energy required to break a specific chemical bond.
Burette - CORRECT ANSWER -
A long glass tube with a tap at one end and markings to show volumes of liquid; used to add precisely
known volumes of liquids to a solution in a conical flask below it.
Carbon footprint - CORRECT ANSWER -
The total amount of carbon dioxide and other greenhouse gases emitted over the full life cycle of a pr
oduct, service or event.
Categoric variable - CORRECT ANSWER -
Categoric variables have values that are labels. For example types of material.
Catalyst - CORRECT ANSWER -
A substance that speeds up a chemical reaction by providing a different pathway for the reaction that
has a lower activation energy. The catalyst is chemically unchanged at the end of the reaction.
Catalytic converter - CORRECT ANSWER -Fitted to exhausts of vehicles to reduce pollutants released.
Cathode - CORRECT ANSWER -The negative electrode in electrolysis.
Ceramics - CORRECT ANSWER -
Materials made by heating clay, or other compounds, to high temperatures (called firing) to make hard
, but often brittle, materials, which make excellent electrical insulators.
Chromatography - CORRECT ANSWER -
The process whereby small amounts of dissolved substances are separated by running a solvent along
a material such as absorbent paper.
Climate change - CORRECT ANSWER -
The change in global weather patterns that could be caused by excess levels of greenhouse gases in th
e atmosphere.
WITH CORRECT ANSWERS 2026-2027
Accurate - CORRECT ANSWER -
A measurement is considered accurate if it is judged to be close to the true value.
Acid - CORRECT ANSWER -
When dissolved in water, its solution has a pH value less than 7. Acids are proton (H+ ion) donors.
Activation energy - CORRECT ANSWER -The minimum energy needed for a reaction to take place.
Akali metal - CORRECT ANSWER -Elements in Group 1 of the periodic table.
Alkali - CORRECT ANSWER -Its solution has a pH value more than 7.
Alkane - CORRECT ANSWER -
Saturated hydrocarbon with the general formula CnH2n+2, for example, methane, ethane, and propan
e.
Alkene - CORRECT ANSWER -Unsaturated hydrocarbon which contains a carbon-
carbon double bond. Its general formula is CnH2n, for example, ethene, C2H4.
Alloy - CORRECT ANSWER -A mixture of two or more elements, at least one of which is a metal.
Anhydrous - CORRECT ANSWER -Describes a substance that does not contain water.
Anode - CORRECT ANSWER -The positive electrode in electrolysis.
Anomalies - CORRECT ANSWER -
Results that do not match the pattern seen in the other data collected or are well outside the range o
f other repeat readings (outliers).
,Aqueous solution - CORRECT ANSWER -The mixture made by adding a soluble substance to water.
Atmosphere - CORRECT ANSWER -The relatively thin layer of gases that surround planet Earth.
Atom - CORRECT ANSWER -
The smallest part of an element that can still be recognised as that element.
Atom - CORRECT ANSWER -
A measure of the amount of starting materials that end up as useful products.
Atomic number - CORRECT ANSWER -
The number of protons (which equals the number of electrons) in an atom. It is sometimes called the
proton number.
Avagadro constant - CORRECT ANSWER -
The number of atoms, molecules, or ions in a mole of any substance (i.e., 6.02 × 1023 per mol).
Balanced symbol equation - CORRECT ANSWER -
A symbol equation in which there are equal numbers of each type of atom on either side of the equat
ion.
Base - CORRECT ANSWER -
The oxide, hydroxide, or carbonate of a metal that will react with an acid, forming a salt as one of the
products. (If a base dissolves in water it is called an alkali). Bases are proton (H+ ion) acceptors.
Biodegradable - CORRECT ANSWER -Materials that can be broken down by microorganisms.
Biofuel - CORRECT ANSWER -Fuel made from animal or plant products.
Blast furnace - CORRECT ANSWER -
The huge reaction vessels used in industry to extract iron from its ore.
, Bond energy - CORRECT ANSWER -The energy required to break a specific chemical bond.
Burette - CORRECT ANSWER -
A long glass tube with a tap at one end and markings to show volumes of liquid; used to add precisely
known volumes of liquids to a solution in a conical flask below it.
Carbon footprint - CORRECT ANSWER -
The total amount of carbon dioxide and other greenhouse gases emitted over the full life cycle of a pr
oduct, service or event.
Categoric variable - CORRECT ANSWER -
Categoric variables have values that are labels. For example types of material.
Catalyst - CORRECT ANSWER -
A substance that speeds up a chemical reaction by providing a different pathway for the reaction that
has a lower activation energy. The catalyst is chemically unchanged at the end of the reaction.
Catalytic converter - CORRECT ANSWER -Fitted to exhausts of vehicles to reduce pollutants released.
Cathode - CORRECT ANSWER -The negative electrode in electrolysis.
Ceramics - CORRECT ANSWER -
Materials made by heating clay, or other compounds, to high temperatures (called firing) to make hard
, but often brittle, materials, which make excellent electrical insulators.
Chromatography - CORRECT ANSWER -
The process whereby small amounts of dissolved substances are separated by running a solvent along
a material such as absorbent paper.
Climate change - CORRECT ANSWER -
The change in global weather patterns that could be caused by excess levels of greenhouse gases in th
e atmosphere.
