Laboratory
Test 1. Hold a burning splint at the mouth of the test tube
Write what you saw for each test. The expected result shows once you have done it.
| Gas | Test | Positive result |
|---|---|---|
| H₂ | Burning splint | Squeaky pop |
| O₂ | Glowing splint | Relights/rekindles |
| CO₂ | Limewater | Turns milky |
| NH₃ | Moist red litmus | Turns blue |
| Cl₂ | Damp blue litmus | Turns red, then bleaches |
| SO₂ | Acidified K₂Cr₂O₇ | Orange turns green |
| HCl | Moist blue litmus | Turns red |
| NO₂ | Observation | Brown gas visible |