This topic summary covers Topic Summary: Water Treatment within Water Treatment for GCSE Chemistry. Revise Water Treatment in Using Resources for GCSE Chemistry with 20 exam-style questions and 15 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 13 of 13 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 13 of 13
Practice
20 questions
Recall
15 flashcards
Topic Summary: Water Treatment
Key Terms
- Potable water: Safe to drink — not the same as pure water
- Sterilisation: Killing microorganisms (e.g. by chlorination)
- Distillation: Heating to steam then condensing — removes all dissolved substances but uses lots of energy
- Desalination: Removing salt from seawater — by distillation or reverse osmosis
- Sedimentation: Particles settle under gravity in tanks
Must-Know Facts
- 4 stages: Screening → Sedimentation → Filtration → Chlorination (SSFC)
- Chlorination kills bacteria and pathogens
- Potable water ≠ pure water (still has dissolved minerals)
- Desalination is expensive due to high energy use
- Sewage treatment: Primary (physical) → Secondary (biological) → Tertiary (chemical, HT)
- Sludge from sewage treatment produces methane gas for energy