Key terms & definitions

The energy required to change one kilogram of a substance from solid to liquid with no change in temperature. The same amount is released when one kilogram freezes.

The specific latent heat for a change between the liquid and vapour states.

The energy required to change one kilogram of a substance from liquid to vapour with no change in temperature. The same amount is released when one kilogram condenses.

The entity being counted, such as an atom, molecule, ion or formula unit.

The objects being counted, such as atoms, molecules, ions, electrons or formula units.

A piece of material being examined, such as a thin sample of plant or animal tissue.

A biological sample prepared for examination, such as a thin layer of onion tissue on a microscope slide.

Single-photon emission-computed tomography: a scanning technique used in this study to measure regional cerebral blood flow.

Visually or aurally striking display that engages spectators through its sensory impact, rather than only through the events of the story.

A person who watches a sporting event, either in person or through media coverage.

An individual member of a film’s audience.

The way a film brings viewers close to a character’s experiences or perspective. This need not mean that viewers approve of the character’s actions.

An ion that remains unchanged during a reaction and does not appear in the ionic equation.

An ion that remains unchanged during a reaction and can be cancelled from both sides when writing an ionic equation.

Sport watched by an audience, whether at the event or through the media.

One narrow band of light at a particular wavelength in an emission spectrum.

A line at a particular wavelength in a spectrum, produced or absorbed by a particular element.

A pattern of particular wavelengths emitted or absorbed by matter, used to identify shifts in light from a galaxy.

A ghost or supernatural apparition.

An instrument that separates emitted light into its different wavelengths.

The study of how matter emits, absorbs or interacts with electromagnetic radiation, used to obtain information about a substance.

A display of the intensity of electromagnetic radiation at different wavelengths.

Reflection from a smooth surface in a single direction.

Buying an asset in the hope of making a profit from changes in its price.

Words identifying who speaks, and sometimes how, such as ‘Maya whispered’ or ‘he asked’.

The distance travelled per unit of time, without a direction; measured in metres per second (m/s).

The distance travelled per unit time, usually measured in metres per second (m/s).

Distance travelled per unit of time.

The actual rate at which data is transferred, measured in bits per second.

The ability to move the body, or a body part, quickly.