This definitions covers Key Definitions within Water Treatment for GCSE Chemistry. Revise Water Treatment in Using Resources for GCSE Chemistry with 23 exam-style questions and 15 flashcards. This topic shows up very often in GCSE exams, so students should be able to explain it clearly, not just recognise the term. It is section 9 of 14 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
📖 Key Definitions
Potable water: Water that is safe to drink — it is not the same as pure water. Potable water can contain dissolved minerals and salts, but must be free from harmful microorganisms and have acceptable levels of dissolved substances.
Sterilisation: The process of killing or removing microorganisms from water, typically done by adding chlorine, using UV light, or using ozone treatment.
Distillation: A purification technique in which water is heated to produce steam, which is then condensed back to liquid. Distillation removes all dissolved substances but requires large amounts of energy.
Desalination: The process of removing salt and dissolved minerals from seawater or brackish water to produce potable water. Methods include distillation and reverse osmosis.
Sedimentation: A stage in water treatment where water is held in large tanks so that heavy particles settle out under gravity, forming a layer of sludge at the bottom.
Practice questions for Water Treatment
What does the term 'potable water' mean?
Explain what happens to the sewage sludge produced during waste water treatment, and why this process is useful.