Question

Waste Water contaminated by organic waste can be treated by

microorganisms naturally and in this process-

(A) DO increases and BOD decreases

(B) DO decreases and BOD Increases

(C) DO increases and BOD increases

(D) DO decreases and BOD decreases​

Answer 1

Answer:

(A) DO increases and BOD decreases.

Explanation:

DO is the dissolved oxygen in water and BOD is the biological oxygen demand.

DO of waste water is low, because water is polluted and there is less oxygen in polluted water.

BOD means biological oxygen demand, which is the amount of oxygen that bacteria will require to digest the waste from polluted body and make it less polluted.

BOD of waste water is high because it is more polluted.

when we treat waste water by micro organisms, its DO starts increasing(it becomes less polluted) and BOD starts decreasing ( bacteria will require less oxygen to convert waste to normal water because waste is less now)