question_answer 22)

  BOD of waste water is estimated by measuring the amount of (a) total organic matter                                                 (b) biodegradable organic matter (c) oxygen evolution                                                      (d) oxygen consumption

Answer:

                  (d) BOD (Biochemical Oxygen Demand) refers to the amount of the oxygen that would be consumed if all the organic matter in one litre of water were oxidized by bacteria .Other options (a) (b) and (c) are incorrect,