A chemist divides a sample of a single gas into four portions. The gas is known to be hydrogen, oxygen, carbon dioxide or chlorine. Three portions are tested.
| Test | Observation |
|---|---|
| A glowing splint is lowered into the gas | The splint does not relight |
| The gas is bubbled through fresh limewater | The limewater remains clear and colourless |
| Damp blue litmus paper is held in the gas | The paper remains blue |
Explain which gas the sample contains.
Describe how the fourth portion could be used to confirm the identification of the gas.
89 exam-style questions on AQA GCSE Chemistry 8.2 Identification of common gases, covering 8.2.1 Test for hydrogen, 8.2.2 Test for oxygen, 8.2.3 Test for carbon dioxide, and 8.2.4 Test for chlorine. Each one has a worked solution and a mark scheme showing where the marks go.