Here are the tests for the different gases, and the positive test results:
Gas | Positive Test Results |
ammonia, NH₃ | turns damp red litmus paper blue |
carbon dioxide, CO₂ | turns limewater milky |
chlorine, Cl₂ | bleaches damp litmus paper |
hydrogen, H₂ | ‘pops’ with a lighted splint |
oxygen, O₂ | relights a glowing splint |
sulfur dioxide, SO₂ | turns acidified aqueous potassium manganate(VII) from purple to colourless |
Watch this video here for the tests for the above gases: