The particle model

Matter is made up of small particles called atoms. Atoms can exist on their own or together as molecules. Atoms are very small and around 100,000,000 of them side by side would measure 1 centimetre.

Changes in a material's temperature or state of matter are caused by changes to the internal energy. The energy required by different materials depends on their 'heat capacity' and 'latent heat'.

See what happens when states of matter change with this interactive activity designed for the GCSE Edexcel combined science specification.

Gases take up more space than solids or liquids and their particles are moving much faster. The temperature, pressure and volume of gases are all related.

Understanding how to approach exam questions helps to boost exam performance. Questions will include multiple choice, structured, using mathematical skills, and extended writing.