test for gases

• test for hydrogen:

  • lit splint held at open end of test tube
  • if hydrogen present, squeaky pop will be heard
  • pop comes from hydrogen burning quickly with oyxgen to from water
• test for oxygen:

  • glowing splint placed inside test tube
  • if oxygen present, splint will relight
• test for carbon dioxide:

  • bubbling through or shaking carbon dioxide through lime water (calcium hydroxide) turns limewater cloudy
• test for chlorine:

  • chlorine bleaches damp litmus paper, turning paper white
  • the litmus paper may firstly turn red because chlorine is acidic