This exam tips covers Exam Tips: Water Treatment 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 13 of 14 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
💡 Exam Tips: Water Treatment
🎯 Common Question Types:
- Order the stages of water treatment (2 marks)
- Explain the purpose of one stage (2 marks)
- Define potable water (1 mark)
- Compare distillation and reverse osmosis (3-4 marks)
- Explain why potable water is not pure water (2 marks)
📝 Key Command Words:
- State: Give a factual answer — no explanation needed
- Explain: Give the reason why — e.g. "Chlorine kills pathogens because..."
- Compare: Give both similarities AND differences between two methods
- Evaluate: Weigh up advantages and disadvantages, then give a conclusion
⚠️ Common Mistakes to Avoid:
- Saying potable water is pure water — it is not
- Saying filtration kills bacteria — it does not; chlorination does
- Confusing sedimentation and filtration — sedimentation uses gravity, filtration uses barriers
- Forgetting that distillation requires large amounts of energy (making it expensive)
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.
Quick recall flashcards
What is potable water?
Water that is safe to drink (low levels of dissolved salts and microbes)
Name two ways to conserve water at home
Low-flow taps/showers, dual-flush toilets, fix leaks, rainwater harvesting