Key terms & definitions

A change involving chemical reactions that alter substances in food, such as sugar browning during caramelisation.

A substance that helps protect the body by killing or breaking down pathogens.

A substance produced by the body that destroys pathogens or inhibits them through chemical action.

Energy associated with the arrangement of particles in a substance or reacting system, which can be transferred during a chemical reaction.

The energy stored in a battery's chemicals that decreases as the battery powers a device.

Energy stored chemically, for example in fuel, food or a battery.

A treatment using chemicals to change a textile's properties or deposit a substance on its surface.

A symbolic representation that identifies the elements in a substance and their relative proportions.

A combination of element symbols and numbers showing which elements a substance contains and their fixed proportions.

A representation using chemical symbols and numbers to show which elements a substance contains and the relative numbers of their atoms.

Describes a substance that is very unlikely to take part in chemical reactions.

Very unreactive chemically under ordinary conditions.

Able to resist reaction with other substances.

Having the same chemical identity and composition as before.

A simplified representation used to explain selected features of a substance or process.

Features that describe how a substance behaves in chemical reactions, such as the kinds of compounds it forms.

A characteristic describing how a substance reacts to form other substances.

A characteristic describing how a substance reacts to form different substances.

A characteristic describing how a substance reacts to form new substances, such as its tendency to corrode.

Cooking woodchips with chemicals to remove lignin and separate the fibres.

An ingredient that produces carbon dioxide through a chemical reaction, such as baking powder or bicarbonate of soda used with an acid.

A process in which atoms are rearranged to form one or more new substances.

A process in which one or more new substances are formed, often with a detectable energy change.

A measure of how readily a substance undergoes chemical reactions.

A drawing or model that stands for a chemical structure while showing selected features of it.

The ability to withstand contact with particular chemicals without unacceptable damage or deterioration.

A chemical treatment that reduces later shrinkage, for example by modifying or coating wool's surface scales to limit felting.

Any atom, molecule, ion or formula unit represented in a chemical calculation or equation.

A particular type of atom, ion or molecule involved in a chemical reaction.

An energy store that can decrease during chemical reactions, such as those involving food or a fuel reacting with oxygen.