What is a catalyst?
What is a catalyst?
A catalyst is a substance that increases the rate of a reaction without being used up. It is chemically unchanged at the end, so it can be recovered and reused.
Step-by-step lessons on Edexcel GCSE Chemistry 8.1.3 Catalysts and enzymes. Each one builds up to exam-style questions. Nail the core quantitative topics — moles, balancing equations and calculations — early on, since they underpin higher-tier questions across every paper and topic.