Potable water is water that is suitable for drinking - Edexcel - GCSE Chemistry Combined Science - Question 2 - 2022 - Paper 1
Question 2
Potable water is water that is suitable for drinking.
(a) River water can be treated to make it potable. Chlorination, filtration and sedimentation are three of the... show full transcript
Worked Solution & Example Answer:Potable water is water that is suitable for drinking - Edexcel - GCSE Chemistry Combined Science - Question 2 - 2022 - Paper 1
Step 1
Which row of the table shows these three processes in the order in which they are carried out?
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Answer
The correct order for treating river water is chlorination, sedimentation, followed by filtration. Therefore, the answer is B:
first
second
third
B
chlorination
sedimentation
filtration
Step 2
State the reason why chlorine is added during the water treatment.
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Answer
Chlorine is added during water treatment to kill harmful microorganisms and bacteria present in the water. This ensures that the water becomes safe for human consumption.
Step 3
Describe how sedimentation is carried out.
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Answer
Sedimentation is carried out by allowing the water to stand in a tank or basin for a period of time. During this period, heavier particles and impurities settle to the bottom due to gravity. The clarified water, now free from most solid impurities, can be collected from the top for further treatment.
