A student investigates the rate of reaction between sodium thiosulfate solution, Na2S2O3\text{Na}_2\text{S}_2\text{O}_3Na2S2O3, and dilute nitric acid, HNO3\text{HNO}_3HNO3.
Na2S2O3(aq)+2HNO3(aq)→2NaNO3(aq)+H2O(l)+SO2(g)+S(s) \text{Na}_2\text{S}_2\text{O}_3(\text{aq}) + 2\text{HNO}_3(\text{aq}) \rightarrow 2\text{NaNO}_3(\text{aq}) + \text{H}_2\text{O}(\text{l}) + \text{SO}_2(\text{g}) + \text{S}(\text{s}) Na2S2O3(aq)+2HNO3(aq)→2NaNO3(aq)+H2O(l)+SO2(g)+S(s)During the reaction, the clear reactants are mixed together and the mixture gradually becomes cloudy.
Explain why the mixture turns cloudy.
127 exam-style questions on Edexcel GCSE Chemistry 8.1 Rates of reaction, covering 8.1.1 Measuring and interpreting rates of reaction, 8.1.2 Collision theory and the factors affecting rate, and 8.1.3 Catalysts and enzymes. Each one has a worked solution and a mark scheme showing where the marks go.