40 exam-style questions on AQA GCSE Chemistry 9.2 Carbon dioxide and methane as greenhouse gases, covering 9.2.1 Greenhouse gases, 9.2.2 Human activities which contribute to an increase in greenhouse gases in the, 9.2.3 Global climate change, and 9.2.4 The carbon footprint and its reduction. Each one has a worked solution and a mark scheme showing where the marks go.