water required practical

• 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?

  pH not equal to 7
• How do you check the pH of water?

  Using universal indicator paper
• What happens if the pH is not 7?

  The water contains dissolved acid or alkali
• 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 is the purpose of heating the water in the evaporating basin?

  To evaporate the water
• What indicates that the water sample contained dissolved solids?

  The mass of the basin increases
• What does it mean if the mass of the evaporating basin does not increase?

  The water sample could be pure
• What may still be present in the water even if it appears pure?

  Dissolved gases
• What is the method used to purify water by distillation?

  Heating water to create vapor
• What equipment is used in the distillation process?

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

  It evaporates and forms steam
• What occurs when water vapor enters the cold test tube?

  It condenses back into liquid water
• What is distilled water?

  Water with no dissolved solids
• What is the pH of distilled water?

  7
• 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 steam.
  3. Steam travels through a delivery tube.
  4. Steam condenses in a cold test tube.
  5. Collect distilled water, which is pure.