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 end to end would measure one centimetre.

For AQA GCSE Chemistry, the specific details of how ammonia is made using the Haber process need to be known, as well as an ability to apply the principles on this page to an unfamiliar new ...

Remember taking science exams when you were at school? Year 11 pupils across the West Midlands are taking their GCSEs at the moment. We've looked at the type of questions students are likely to be set ...