If a 2% solution of sewage sample is incubated for 5 days at 20°C and the dissolved oxygen depletion was found to be 8 mg/l. The BOD of the sewage is_________________?

Related Mcqs:

1. If 2% solution of a sewage sample is incubated for 5 days at 20°C and depletion of oxygen was found to be 5 ppm, B.O.D. of the sewage is____________________?

   A. 200 ppm B. 225 ppm C. 250 ppm D. None of these...

2. If the depletion of oxygen is found to be 5 ppm after incubating a 2.5% solution of sewage sample for 5 days at 21°C, B.O.D. of the sewage is_____________________?

   A. 50 ppm B. 100 ppm C. 150 ppm D. 200 ppm...

3. If the depletion of oxygen is found to be 2.5 mg/litre after incubating 2.5 ml of sewage diluted to 250 ml for 5 days at 20°C, B.O.D. of the sewage is_________________?

   A. 50 mg/l B. 100 mg/l C. 150 mg/l D. 250 mg/l...

4. 3.0 ml of raw sewage is diluted to 300 ml. The D.O. concentration of the diluted sample at the beginning of the test was 8 mg/l. After 5 day-incubation at 20°C, the D.O. concentration was 5 mg/l. The BOD of raw sewerage is______________________?

   A. 100 mg/l B. 200 mg/l C. 300 mg/l D. 400 mg/l...

5. Bio-chemical oxygen demand (BOD) for the first 20 days in generally referred to_______________?

   A. Initial demand B. First stage demand C. Carbonaceous demand D. All of these...

6. For the survival of fish in a river stream, the minimum dissolved oxygen is prescribed________________?

   A. 3 ppm B. 4 ppm C. 5 ppm D. 10 ppm...

7. Which of the following pumps in used to pump sewage solids with liquid sewage without clogging the pump is ?

   A. Centrifugal pump B. Pneumatic ejector C. Reciprocating pump D. None of these...

8. The density of population over 40 hectares is 250/hectare. If water supply demand per day is 200 litres and sewage discharge is 80% of water supply, the sewage flow in sewers of separate system, is_____________________?

   A. 0.05552 cumec B. 0.05554 cumec C. 0.05556 cumec D. 0.0556 cumec...

9. For trunk sewers more than 1.25 m in diameter, the ratio of the maximum daily sewage flow to the average daily sewage flow is assumed________________?

   A. 1.5 B. 2.0 C. 2.5 D. 3.0...

10. For sewer mains of 0.5 to 1 m diameter, the ratio of maximum daily sewage flow to the average daily sewage flow is assumed__________________?

    A. 1.5 B. 2.0 C. 2.5 D. 3.0...