potable water

• What is the main difference between potable water and pure water?

  Potable water contains dissolved substances, while pure water contains no dissolved substances at all.
• Why is drinking water essential for human life?

  Because humans cannot drink any water they find; it must have low levels of dissolved salts and microbes.
• What term do scientists use to describe water that is safe to drink?

  Potable water.
• What are the steps used to produce potable water from fresh water?

  1. Use a good source of fresh water.
  2. Pass the water through filter beds to remove materials.
  3. Sterilize the water to kill microbes, typically using chlorine in the UK.
• What is the role of filter beds in the production of potable water?

  To remove materials such as leaves and suspended particles.
• What methods are used to sterilize potable water in the UK?

  Chlorine is used to sterilize potable water in the UK.
• What alternatives to chlorine are used for sterilizing water in some parts of the world?

  Ozone or ultraviolet light are used instead.
• What is a significant source of potable water in the UK?

  Rainwater.
• Why is fresh water scarce in many places around the world?

  Because the only available water may be too salty to drink, such as seawater.
• What is the process of desalination used for?

  To reduce the levels of dissolved minerals in salty water to an acceptable level for potable water.
• What are two methods of desalination mentioned in the study material?

  1. Distillation
  2. Reverse osmosis
• What is a drawback of both distillation and reverse osmosis processes?

  Both processes require very large amounts of energy, making them expensive.
• Where can you find questions on potable water for revision?

  In the revision workbook linked in the video.