Measuring the Volume of Gases

• What is used to seal a gas reaction mixture?

  A bung
• Why is using a gas syringe more accurate?

  Some gases dissolve in water
• What is the purpose of the delivery tube in gas collection?

  To transport collected gas
• How is gas collected in a measuring cylinder?

  Gas displaces an equal volume of water
• How is the measuring cylinder positioned during gas collection?

  Filled and upturned in water
• How do you calculate the amount of gas collected?

  Difference between initial and final volumes
• What are the steps to measure the volume of gas produced in a reaction?

  1. Seal the reaction mixture with a bung.
  2. Use a gas syringe for accuracy.
  3. Connect a delivery tube to the measuring cylinder.
  4. Collect gas by displacing water.
  5. Measure the difference in cylinder volumes.
• What are the advantages of using a gas syringe over a measuring cylinder?

  • More accurate measurement
  • Avoids gas dissolution in water
  • Easier to read gas volume directly