Chemistry Reactions

Acid

A substance that produces hydrogen ions (H+) when dissolved in water

Alkali

A soluble base

Atomic Number

The number of protons in the nucleus of an atom

Base

A substance that accepts hydrogen ions (H+) or that dissolves to release hydroxide ions (OH-).

Compound

A substance made from two or more different elements that have been chemically joined

Combustion

A chemical process that occurs when fuel is burned and reacts with oxygen to release energy.

Complete combustion

A combustion reaction that occurs when fuel reacts with oxygen to produce carbon dioxide and water

Electrons

A negatively charged particle found in electron shells the move around the outside of the nucleus

Element

A pure substance made up of only one kind of atom.

Ion

A charged (positive or negative) atom or group of atoms.

Incomplete combustion

A combustion reaction that occurs when fuel reacts with a limited supply of oxygen to produce carbon or carbon monoxide, water and some energy.

Insoluble

A substance that does not dissolve in a liquid (solvent)

Mass number

The total number of protons and neutrons in a nucleus

Nucleus

Central part of an atom that consists of protons and neutrons

Neutrons

A particle found inside the nucleus of an atom, it has no charge ( is neutral)

Neutralisation

A chemical reaction between an acid and a base which produces a more neutral solution (salt and water)

Precipitate

An insoluble solid that forms when substances in a solution are mixed

Protons

Positively charged particle found inside the nucleus of an atom

Soluble

A substance that dissolves in a liquid (solvent)

Universal indicator

A pH indicator that shows various colour changes over a wide range pH values to indicate the acidity or alkalinity of solutions.