Edexcel GCSE Combined Science key terms

How effectively a treatment produces its intended effect.

The ratio of useful energy transferred by a device to the total energy supplied to it.

A reversible change of shape: the object returns to its original shape when the deforming forces are removed.

Energy stored in an object because it has been elastically stretched or compressed.

A repeated variation in current or potential difference in an electrical circuit.

Opposition to the flow of electric current through a component.

An electrical property carried by particles such as protons and electrons. The amount of charge transferred is measured in coulombs (C).

The rate of flow of electric charge. In a metal, the moving charges are electrons.

A conductor through which current enters or leaves an electrolyte.

The decomposition of an ionic compound using an electric current.

An ionic substance that conducts electricity when molten or dissolved in water because its ions can move.

A magnet whose magnetic field is produced by an electric current, usually flowing through a coil of wire.

The production of a potential difference across a conductor when it cuts magnetic field lines or when the magnetic field passing through a coil changes.

The continuous range of electromagnetic radiation, from radio waves to gamma rays.

A transverse wave that transfers energy from a source to an absorber and can travel through a vacuum.

A negatively charged particle found around an atom’s nucleus, with relative charge −1 and a very small relative mass of about 0.0005.

The arrangement of electrons in an atom's shells, for example 2,8 for neon.

An instrument that uses a beam of electrons to produce images with much higher resolution than a light microscope.

One of the allowed set distances from the nucleus at which an electron can exist in the GCSE atomic model.

An energy level occupied by electrons around an atom’s nucleus.

The reduction in the attraction between the nucleus and an outer or incoming electron caused by electrons in inner shells.

A stem cell in an early embryo that can differentiate into any type of specialised body cell.

A formula showing the simplest whole-number ratio of atoms of each element in a compound.

A group of cells that produces and releases hormones directly into the bloodstream.

A change or reaction in which heat energy is taken in from the surroundings.

A reaction that takes in energy from the surroundings.

The point in a titration at which the indicator shows its lasting colour change.