What is an ion?
What is an ion?
An ion is an atom, or group of atoms, with an overall electrical charge because it has lost or gained electrons. A neutral atom has equal numbers of protons and electrons, so the positive and negative charges cancel.
Step-by-step lessons on Edexcel GCSE Chemistry 2.3.1 Ions and the formation of ionic bonds. 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.