Chemistry- C10 Part C

1. Producing water, In ... : Desalination- Test pH with titration. Test water for sodium chloride with flame test and halide test. Use distillation for water and retest pH to see if its neutral. Reverse Osmosis- Salty water is passed through a membrane (3, 9, 6)
4. ... uses less energy than water... : 4- Sludge is broken down by anaerobic digestion. 5- Anaerobic digestion produces methane which is then used in fertilisers. 6- Water containing toxic substances have additional stages of ... by adding chemicals (9)
6. ... from domestic or agricultural sources has to be treated or if not, it could pose health risks. The Haber process produces a lot of ... (5, 5)
7. Producing water, In ... :Filtration- Wire mesh screens out large twigs and sand or gravel beds filter out smaller particles. Sterilisation- Water sterilised to kill any bacteria or microbes. Using chlorine, UV light or ozone. (3, 2)
8. Life Cycle Assessments (LCA) can be ... depending on the person carrying out the assessment. Some other problems include the pollution produced and the energy used (6)
9. Both techniques in hot countries require a lot of ... (6)

2. ... uses less energy than water ... : 1-Sewage is screened to remove large material or dirt. 2- Undergoes sedimentation, sludge produced at bottom. 3- Effluent (stuff at the top) is treated by aerobic digestion (9)
3. ... metals is important, their production uses lots of energy. ... uses much less energy. Metals can be ... by melting and remoulding. Glass can be ... by being crushed and reshaped (9)
5. Glass bottle are ... without reshaping (6)
10. ... is freshwater collected as surface water or ground water- the source of fresh water depends on location. In dry countries, there isn't enough water so seawater must be used to make potable water (9)

Get Revising