P2 water

• What should you be able to describe by the end of the video?

  How to analyze and purify water
• What is potable water?

  Water that is safe to drink
• How does potable water differ from pure water?

  Potable water may contain dissolved solids
• What is the pH of pure water?

  7
• What indicates that a water sample is not pure?

  If the pH is not seven
• How do you check the pH of water?

  Using universal indicator paper
• What happens if the pH is seven?

  The water could still contain dissolved solids
• What is the first step in testing for dissolved solids in water?

  Weigh an empty evaporating basin
• What do you do after weighing the empty evaporating basin?

  Fill it with the water sample
• What indicates the presence of dissolved solids after evaporation?

  An increase in the mass of the basin
• What does it mean if the mass of the evaporating basin does not increase?

  The water did not contain dissolved solids
• What may still be present in the water even if it contains no dissolved solids?

  Dissolved gases
• What is the purpose of distillation in water purification?

  To separate pure water from dissolved solids
• What equipment is used in the distillation process?

  A conical flask and delivery tube
• What happens to water when it is heated in distillation?

  It evaporates and forms water vapor
• What is formed when water vapor condenses?

  Liquid distilled water
• What is the pH of distilled water?

  7
• Why is distilled water considered pure?

  It contains no dissolved solids
• What are the steps to analyze a sample of water for purity?

  1. Check the pH using universal indicator paper.
  2. Weigh an empty evaporating basin.
  3. Fill the basin with the water sample.
  4. Heat the water until it evaporates.
  5. Weigh the basin again to check for dissolved solids.
• What is the process of purifying water by distillation?

  1. Heat the water sample in a conical flask.
  2. Water evaporates and forms vapor.
  3. Vapor travels through a delivery tube.
  4. Vapor condenses in a cold test tube.
  5. Collect distilled water, which is pure.