Two Ways of Measuring Rates of Reactions

• What is one way to measure the rate of reaction?

  Volume of gas given off
• What does the bung do in the gas collection setup?

  Stops the gas from escaping
• What is the independent variable in the gas volume experiment?

  Concentration of acid
• What is the dependent variable in the gas volume experiment?

  Volume of gas released
• How does the volume of gas relate to the rate of reaction?

  More gas indicates a faster reaction rate
• What is the procedure for measuring gas volume in a reaction?

  • Use a gas syringe
  • Measure at regular intervals
  • Use a stopwatch
• What is the second method of measuring reaction rates mentioned?

  Precipitation method
• What happens to the initial solution in the precipitation method?

  It is transparent
• What is the independent variable in the precipitation experiment?

  Concentration of acid
• What is the dependent variable in the precipitation experiment?

  Time for cross to disappear
• How does the speed of the cross disappearing relate to the rate of reaction?

  Faster disappearance indicates a faster reaction
• What do both experiments demonstrate about acid concentration and reaction rate?

  Higher acid concentration increases reaction rate
• What are the key components of the gas collection experiment?

  • Magnesium metal
  • Dilute hydrochloric acid
  • Conical flask
  • Delivery tube
• What are the key components of the precipitation experiment?

  • Dilute hydrochloric acid
  • Sodium thiosulfate
  • Cross drawn on paper
• What are the subjective aspects of the precipitation experiment?

  • Results depend on individual perception
  • Time taken for cross to disappear varies