EDUCATION UGC NET
ENVIRONMENTAL STUDIES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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6.5 to 7.5
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7.0
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6.5 to 8.5
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6.0 to 8.5
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Detailed explanation-1: -Permissible limit: For drinking water, permissible limit of pH is 7 to 8.5, but it should not be less than 6.5 and not greater than 9.2, hence Permissible values of pH for public supplies may range between 6.6 to 8.5.
Detailed explanation-2: -The pH scale ranges from 0 to 14. In general, a water with a pH < 7 is considered acidic and with a pH > 7 is considered basic. The normal range for pH in surface water systems is 6.5 to 8.5 and for groundwater systems 6 to 8.5.
Detailed explanation-3: -There has been no evidence of harm found in drinking water with a pH of between 7 and 8.5. (Interesting to note: The pH of human blood is a little on the basic side, 7.365.) When the PH of water becomes greater than 8.5, water taste can become more bitter.
Detailed explanation-4: -Water with a pH level between 6 and 8.5 is safe to drink because it is neither acidic nor alkaline enough to be dangerous in the human body. Water with a pH of less than 6 can be corrosive and filled with toxic metals.