Potassium chlorate decomposes according to the equation:
2KClO3→2KCl+3O22\text{KClO}_3 \rightarrow 2\text{KCl} + 3\text{O}_22KClO3→2KCl+3O2
The relative formula mass, MrM_rMr, of KClO3\text{KClO}_3KClO3 is 122.5. At room temperature and pressure, one mole of any gas occupies 24 dm3.
Calculate the volume, in cm3\text{cm}^3cm3, of oxygen produced when 4.90 g of potassium chlorate decomposes completely.
100 exam-style questions on AQA GCSE Chemistry 3.5 Use of amount of substance in relation to volumes of gases, covering 3.5.1 Volumes of gases. Each one has a worked solution and a mark scheme showing where the marks go.