Edexcel GCSE Chemistry key terms

Describes a solution with a pH below 7.

A solution that contains hydrogen ions, H⁺, and has a pH below 7.

Rain or other precipitation that is more acidic than normal because acidic gases have dissolved in atmospheric water.

The minimum energy that reacting particles must have for a reaction to occur.

An electrode made from a material that takes part in an electrode reaction.

The mass of product actually obtained and collected in a reaction.

A polymer formed when many unsaturated monomers join without producing another substance.

A reaction in which many monomers containing C=C join to form a polymer, without producing another molecule.

A reaction in which two reactant molecules join to make one product; bromine adds across an alkene's C=C bond.

Respiration that uses oxygen to release energy from glucose.

An organic compound containing a hydroxyl (–OH) functional group.

A soluble base that produces hydroxide ions when dissolved in water.

A metal in Group 1 of the periodic table, such as lithium, sodium or potassium.

The metals in Group 1 of the periodic table, whose reactions with water produce alkaline metal hydroxide solutions and hydrogen.

Describes a solution with a pH above 7.

A solution with a pH above 7 in which the alkali is a source of hydroxide ions, OH⁻.

A saturated hydrocarbon containing only carbon–carbon single bonds.

An unsaturated hydrocarbon containing a carbon–carbon double bond.

The carbon–carbon double bond, $C=C$, that gives alkenes their characteristic reactions.

One of several forms of the same element whose atoms are arranged or bonded differently.

A mixture of two or more elements in which at least one element is a metal.

Steel containing deliberately added metals to alter its properties for a particular use.

A small organic molecule that acts as a building block for proteins.

A colourless, basic gas with the formula $\mathrm{NH_3}$.

A dissolved ion with the formula $NH_4^+$; it is different from ammonia gas, $NH_3$.

The salt $\mathrm{NH_4NO_3}$, used as a nitrogen-containing fertiliser.

A soluble salt containing ammonium ions, NH₄⁺, and sulfate ions, SO₄²⁻.

The amount of substance calculated by dividing its mass in grams by its molar mass in grams per mole.