The Earth's atmosphere today is a mixture of different gases.
Which of these options lists the three most abundant gases in clean, dry air, in order from the highest percentage to the lowest percentage?
oxygen, nitrogen, carbon dioxide
nitrogen, oxygen, argon
nitrogen, carbon dioxide, oxygen
oxygen, nitrogen, argon
97 exam-style questions on Edexcel GCSE Chemistry 9.2 Earth and atmospheric science, covering 9.2.1 The Earth's early atmosphere, 9.2.2 How the atmosphere evolved, 9.2.3 Chemical test for oxygen, and 9.2.4 The greenhouse effect and climate change. Each one has a worked solution and a mark scheme showing where the marks go.