Chemistry key terms

A consistent effect that shifts measurements away from the true value in the same direction.

The stages, processes and impacts included within an assessment.

A straight line drawn at a chosen point on a curve that follows the curve’s direction there. Its gradient shows the rate of change at that point.

To set a balance reading to zero, usually with an empty container on it, so that the next reading gives only the mass of the material added.

A thin, often discoloured surface layer formed when a metal reacts with its surroundings.

A new or improved practical application of scientific knowledge, such as a product, process or device.

The difference between a measured temperature and the average temperature for a stated reference period.

The difference between the final and initial temperatures, measured in °C in these investigations.

The difference between the final and initial temperatures, calculated using $\Delta T=T_{\text{final}}-T_{\text{initial}}$.

A material's ability to withstand a pulling force without breaking or stretching excessively.

A chemical added to a sample to produce an observable result that helps identify a substance.

A three-dimensional arrangement in which one central atom is joined to four atoms directed towards the corners of a tetrahedron.

The greatest mass of a product predicted from the balanced equation, assuming the reaction proceeds completely and no product is lost.

A value predicted from a model or equation rather than obtained by measuring the result of an actual experiment.

The maximum amount of product predicted from the balanced equation, assuming the relevant reactant forms the expected product without losses.

A material through which thermal energy is transferred readily.

The breaking down of a compound into simpler substances when it is heated.

Electromagnetic radiation emitted by warm objects; the relatively cool Earth emits much of its energy as thermal infrared radiation.

A polymer with strong cross-links between its chains, so it does not melt when heated.

A polymer whose separate chains can move past one another when heated, allowing the material to melt and be reshaped.

A representation showing the spatial arrangement of atoms and bonds in three dimensions.

A representation that shows or suggests height, width and depth.

An arrangement that has length, width and depth.

The solution delivered from the burette during a titration.

A method for measuring the volumes of two solutions that react together by adding one solution to a measured volume of the other until an indicator changes colour.

The volume delivered from the burette during a titration, found by subtracting its initial reading from its final reading.

Thin layer chromatography, in which the supporting surface is coated with a thin layer of material such as silica or aluminium oxide.

The ability to absorb energy and resist cracking or breaking.

Poisonous; able to cause serious harm or death if a sufficient amount enters the body.

A poisonous gas that harms living organisms when inhaled.