Two unlabeled gas cylinders contain gas mixtures, X and Y. One mixture has a composition similar to Earth's early atmosphere, while the other is similar to today's atmosphere.
A student performs tests on both mixtures and records the results in the table below:
| Test | Result with Gas Mixture X | Result with Gas Mixture Y |
|---|---|---|
| Bubble the gas through limewater | Rapidly forms a white precipitate (within 5 seconds) | Slowly forms a faint white precipitate (after 3 minutes) |
| Place a burning wooden splint into the gas | The splint is extinguished immediately | The splint continues to burn |
Explain, using the data in the table, which gas mixture represents the Earth's early atmosphere.
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.
