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Water treatment and potable water
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Water that is safe to drink is called potable water. It is not the same as pure water.
Potable water
Potable water is safe to drink. It still contains some dissolved substances, so it is not chemically pure.
Treating fresh water
Sedimentation: large particles settle.
Filtration: sand beds remove small insoluble particles.
Chlorination: chlorine kills microorganisms.
Filtration: sand beds remove small insoluble particles.
Chlorination: chlorine kills microorganisms.
Water for analysis
Distilled or deionised water is used in chemical analysis, because tap water contains ions that could interfere with results.
Sea water can be made potable by distillation (desalination), but this uses a lot of energy.
Sea water can be made potable by distillation (desalination), but this uses a lot of energy.
Why is chlorine added to drinking water?
- Chlorine kills harmful microorganisms.
Answer: To kill microorganisms.
Potable water is safe to drink but not pure. Treatment: sedimentation, filtration, chlorination. Use distilled water for analysis. Desalination works but needs lots of energy.
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