Chemistry key terms

A substance made from oppositely charged ions held in a giant lattice by strong electrostatic attractions.

The formation of ions from neutral particles when a substance is dissolved or reacts.

The smallest whole-number ratio of each type of ion in an ionic compound.

Compounds with the same molecular formula but different arrangements of atoms.

One of two or more atoms of the same element that have the same number of protons but different numbers of neutrons.

Atoms of the same element with the same number of protons but different numbers of neutrons.

The proportion of an element's atoms that are a particular isotope, often expressed as a percentage.

A systematic set of internationally agreed rules for naming chemical substances.

The energy a particle has because it is moving or vibrating.

A site where waste is buried and stored.

A regular, repeating three-dimensional arrangement of particles extending through a substance.

The principle that no atoms are made or lost during a chemical reaction, so the total mass of all the products equals the total mass of all the reactants.

A solution containing dissolved substances that have been washed or released from a solid material.

Digits written before the first non-zero digit to position the decimal point; they do not count as significant figures.

A qualitative rule stating that when the conditions of a system at equilibrium are changed, the system shifts in the direction that counteracts the change.

A prediction rule: when conditions affecting an equilibrium change, the position shifts in a direction that opposes the change.

A study of the environmental impacts associated with every stage of a product's life, from obtaining raw materials to its end-of-life treatment.

An assessment of the environmental impact of a product across the stages of its life, from obtaining raw materials to its end-of-life treatment.

A wooden stick that is burning with a visible flame.

A sedimentary rock made mainly of calcium carbonate.

An aqueous solution of calcium hydroxide used to test for carbon dioxide.

A weakness or boundary of a model that prevents it from representing or explaining some feature of reality.

A natural resource available in limited amounts that cannot be replaced as quickly as it is used.

The reactant that is completely used up in a reaction and therefore determines the maximum amount of product that can form.

A chart showing the wavelengths of light emitted by a substance as separate lines or peaks.

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

A pattern of separate bright lines at particular wavelengths in light emitted by a substance.

A state of matter in which particles remain close together but are irregularly arranged and can move past one another.

Paper containing a coloured indicator that responds to acidic or alkaline conditions.

A substance used to make otherwise invisible chromatogram spots visible.