Water Pollution - Water Pollution & Portable Water Past Year (2006 - 2015) MCQs Environmental Chemistry (OLD NCERT) Chemistry NEET Practice Questions, MCQs, Past Year Questions (PYQs), NCERT Questions, Question Bank, Class 11 and Class 12 Questions, and PDF solved with answers

Which one of the following statements is not true?

1.	Clean water would have a BOD value of 5 ppm.
2.	Fluoride deficiency in drinking water is harmful. Soluble fluoride is often used to bring its concentration upto 1 ppm.
3.	When the pH of rainwater is higher than 6.5, it is called acid rain.
4.	Dissolved Oxygen (DO) in cold water can reach a concentration upto 10 ppm.

Subtopic: Air Pollution - Acid Rain | Water Pollution - Water Pollution & Portable Water |

77%

From NCERT

NEET - 2013

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