The rate of reaction and the factors affecting it is a key topic in the GCSE chemistry specifications. You need to understand how these different factors such as pressure, concentration, temperature and the presence of a catalyst impact on the equilibrium of a reversible reaction. You need to know the definition of chemical equilibrium and dynamic equilibrium. Whether you are revising for the AQA GCSE chemistry exam or you are sitting the exam with another exam board, you will need to know about rates of reactions and chemical equilibrium. Use our free chemistry resources below to help you revise.