Tests for gases

• Test for Carbon Dioxide (CO2)

  • Bubble the gas through limewater
  • If the gas is carbon dioxide, the limewater will turn cloudy.
• Test for Hydrogen (H2)

  • Hydrogen will make a 'squeaky pop' in the presence of a lit splint
• Test for Oxygen (O2)

  • If a glowing splint is relit, Oxygen is present
• Test for Chlorine (Cl2)

  • Hold a piece of damp blue litmus paper over the gas
  • If the gas is chlorine, the blue litmus paper bleaches, turning white
  • Blue litmus paper -> White litmus paper
• All gas tests should be carried out:

  • Without safety goggles
  • In a fume cupboard
  • With hair tied up