testing for gases

• What are the four gases that you should be able to test for by the end of the video?

  • Hydrogen
  • Oxygen
  • Carbon dioxide
  • Chlorine
• What sound is produced when a burning splint is inserted into hydrogen gas?

  A pop sound
• Why is it important to learn the tests for gases?

  Because these tests could be a new exam topic and are easy to confuse.
• What is the purpose of removing the bomb before testing hydrogen gas with a burning splint?

  • To ensure the test is conducted safely without risk of an explosion.
• What do you use to test for hydrogen gas?

  A burning splint
• What observation indicates the presence of hydrogen gas during the test?

  The burning splint produces a pop sound.
• What do you use to test for oxygen gas?

  A glowing splint
• What reagent is used to test for carbon dioxide gas?

  Lime water
• What happens when a glowing splint is placed into oxygen gas?

  The splint reignites and bursts into flames.
• What is lime water chemically known as?

  $Ca(OH)_2$
• Describe the procedure to test for carbon dioxide gas.

  1. Draw the gas into a plastic pipette.
  2. Bubble the gas into lime water.
  3. If the lime water turns cloudy, the gas is carbon dioxide.
• What chemical dissolves in water to make lime water?

  $Ca(OH)_2$
• If a gas turns lime water cloudy, which gas is present?

  Carbon dioxide
• What material is used to test for chlorine gas?

  Damp litmus paper
• How does chlorine affect damp litmus paper?

  Chlorine bleaches the litmus paper and turns it white.
• What color change occurs in damp litmus paper when chlorine gas is present?

  The litmus paper turns white.