Testing for gases

• Test for hydrogen gas

  1. Remove the bung

  2. Insert a burning splint
• Hydrogen gas

  • Burns rapidly
  • Produces a pop sound
• Test for oxygen gas

  Use a glowing splint
• Oxygen gas


  • Causes the glowing splint to burst into flames
• Test for carbon dioxide gas

  1. Use lime water

  2. Bubble the gas through the lime water
• Carbon dioxide gas

  • Turns lime water cloudy
• Test for chlorine gas


  Insert damp litmus paper
• Chlorine gas


  • Bleaches and turns litmus paper white
• These gas tests are very straightforward but could be new exam content and easy to confuse, so it's important to learn them
• You'll find plenty of questions on testing for gases in the revision workbook