Question

Which of the following physical method is used as germicidal in modern time for the treatment of

drinking water?

(a) Chlorination (b) Treating with potassium permagnate (c) UV radiation​

Answer 1

Answer:

Chlorination is the mordern method

Answer 2

(c) UV radiation is used as germicidal in modern times for the treatment of drinking water.

Process of UV radiation method:

1. UV disinfection methods are used to inactivate protozoa, bacteria and viruses present in contaminated water.
2. A UV light is put into the contaminated water that inactivates microorganisms present. This results in damage to the deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
3. The moment UV light is absorbed by DNA and RNA, dimers cause a fault in the transcription of information. This results in damage to the replication ability of a microorganism.
4. Although the microorganism is still there in the water, they cannot reproduce. Thus, their presence does not cause any harm and the water becomes fit for drinking.

Advantages of UV radiation method:

1. This system disinfects water without adding unnecessary chemicals into the water.
2. It does not result in a change in taste or odour of the water.
3. The method is most useful as it does not result in the removal of beneficial minerals present in the water.

UV radiation has proven to be one of the most effective methods for disinfection of harmful particles present in water and is a safe, reliable and inexpensive germicidal method.