Question

6. All are correct w.r.t. BOD (Biochemical Oxygen
Demand), except
(1) It refers to the amount of oxygen that would be
consumed if all the organic matter in one liter of
water were oxidised by bacteria
(2) The BOD test is a measure of the organic matter
present in the water
(3) The greater the BOD of waste water, less is its
polluting potential
(4) Waste water is treated till BOD is reduced
significantly
7. The Ministru
of​

Answer 1

Answer:

Aquatic Chemistry and Biology

Municipal wastewater consumes O2 in the range from 300 to 1000 mg l−1. After biological treatment, the COD (O2) drops to 20–1000 mg l−1. Landfill leachate can reach up to ρ(O2) of 3000 mg l−1. The COD of surface water normally ranges from 5 to 20 mg

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