S5 Chemistry: Deviations from Raoult's Law

These notes by Ssegujja Benard explain how differences in intermolecular attractions cause liquid mixtures to deviate from Raoult's law. They compare positive and negative deviations through changes in vapour pressure, boiling point, volume and heat transfer, with examples of liquid pairs. The material discusses vapour pressure–composition and boiling point–composition diagrams, including azeotropic points and their interpretation. Questions and exercises ask learners to explain mixture behaviour, identify diagram features and describe fractional distillation at specified compositions. Some exercises refer to accompanying audiovisual explanations.