What formulae and equations tell you
What formulae and equations tell you

A chemical formula shows what atoms or ions are present and their ratio, while a chemical equation shows how reactants turn into products. The order of operations is essential: get the formulae right first, then balance the equation, then add state symbols, and simplify to an ionic equation if required.
Step-by-step lessons on Eduqas A Level Chemistry Formulae and equations. Each one builds up to exam-style questions. Build confidence with atomic structure, bonding and moles calculations early on, since these underpin the more demanding organic mechanisms, equilibrium and practical-analysis topics that dominate Year 2.