Which out of the following does not help in disinfecting water?

  1. Filtration
  2. Chlorine tablets
  3. Alums
  4. Boiling

Answer (Detailed Solution Below)

Option 1 : Filtration
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Detailed Solution

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The correct answer is Filtration.

Key Points

Filtration

  • Filtration is a process used to separate solids from liquids or gases by using a filter medium that allows fluid to pass through but not solid. 
  • Filtration can be mechanical-biological or physical. 
  • It does not help in disinfecting water
  • If you want to disinfect the water you can boil it or you can use alum for chlorine tablets. 

Boiling

  • Boiling is used to kill pathogenic bacteria, viruses, and protozoa

Chlorination

  • Chlorine kills a large variety of microbial waterborne pathogens.
  • Chlorination is the process of adding chlorine to the water to disinfect it and kill pathogens
  • Amount of chlorine required for water disinfection around 1-16 milligrams per litre of water.

Coagulation

  • Alum acts as an electrolyte that helps in settling the suspended matter in water.
  • The process of adding alum to disinfect water is called coagulation
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