Table 1 shows the estimated percentages of different gases in the Earth's early atmosphere compared with the atmosphere today.
| Gas | Percentage (%) in Earth's early atmosphere | Percentage (%) in today's atmosphere |
|---|---|---|
| carbon dioxide | 96.0 | 0.04 |
| nitrogen | 3.0 | 78.0 |
| Gas Q | <0.1 | 21.0 |
| argon | <0.1 | 0.9 |
| methane | 0.5 | <0.001 |
| ammonia | 0.4 | <0.001 |
Explain, using the data in Table 1, the identity of Gas Q.
Practise Edexcel GCSE Chemistry Earth and atmospheric science with exam-style questions for Foundation and Higher tier. 62 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
