Models of the atom
Models of the atom

Atoms are the smallest particles of an element that still keep that element's chemical properties. Scientists use models to explain what atoms are like inside, and these models changed when new evidence appeared.
Step-by-step lessons on OCR GCSE Chemistry Atomic structure. 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.