OCR GCSE Chemistry B key terms

A solution in which a substance is dissolved in water, shown by the state symbol (aq).

A solution in which water is the solvent.

A reasoned case in which evidence and ideas are used to support a conclusion.

The sum of a set of values divided by the number of values.

A condition accepted as true when constructing or using a model, often to simplify the real system.

The layer of gases surrounding a planet.

The smallest particle of an element that retains the chemical properties of that element.

The percentage of the total mass of reactant atoms that the balanced equation places in the desired product.

A scientific representation of an atom used to explain observations and make predictions; it can change when new evidence appears.

The number of protons in the nucleus of an atom; it identifies the element.

The approximate distance from an atom’s nucleus to the outer extent of its electron region.

The people for whom a communication is intended, such as specialist scientists, the public or policy-makers.

The rate calculated over a chosen time interval rather than at one particular moment.

The fixed number of specified particles in one mole: $6.0\times10^{23}\text{ mol}^{-1}$ for these calculations.

The principle that equal volumes of gases at the same temperature and pressure contain equal numbers of particles.

The use of bacteria to release metal compounds from ores or waste material, commonly producing a solution called a leachate.

An equation using chemical formulae in which there are equal numbers of each type of atom on both sides.

A chemical equation with the same number of atoms of each element on both sides.

A symbol equation with the same number of atoms of each element on both sides.

The number written before a formula in a balanced equation, showing the reacting ratio of particles or amounts in moles.

A three-dimensional molecular model in which balls represent atoms and sticks represent bonds between them.

Production of a limited quantity in one run before the next run begins.

An aluminium-rich ore from which aluminium oxide is obtained for aluminium extraction.

A helpful or desirable outcome for an individual, group or the environment.

A smooth line or curve drawn to represent the overall pattern of plotted data.

A judgement or preference that may influence how evidence is interpreted or a decision is made.

An ionic compound containing only two different elements, usually a metal and a non-metal.