The Earth's early atmosphere was very different from the Earth's atmosphere today.
The table shows the composition of dry air today.
| Gas | Percentage (%) of dry air |
|---|---|
| nitrogen | 78 |
| oxygen | 21 |
| argon | 0.9 |
| carbon dioxide | 0.04 |
Name the gas that makes up the largest percentage of dry air today.
Calculate the percentage of dry air today that is gases other than nitrogen and oxygen.
The Earth's early atmosphere was formed from gases released by one natural source. Name this source.
Give the names of the two gases that made up most of the Earth's early atmosphere.
State one difference between the amount of oxygen in the Earth's early atmosphere and the amount of oxygen in the atmosphere today.
35 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.