AQA GCSE Combined Science Trilogy · 8464
Specification 5.6.1.2 · Paper 4
Revise: Factors Affecting Reaction RatesAQA required practical 11 investigates the effect of concentration using two methods: measuring the volume of gas produced, and observing a change in colour or turbidity. Turbidity means cloudiness caused by suspended particles. The disappearing-cross method below uses turbidity, rather than a colour change.