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_____________________?

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 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...

3. 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_________________?

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

4. 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...

5. 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...

6. A cylindrical ejector having its height 2 m fills after every 10 minutes with a peak sewage discharge of 0.0157 cumec. The diameter of the ejector chamber, is_____________________?

   A. 2.30 m B. 2.40 m C. 2.45 m D. 2.50 m...

7. The dimensions of a rectangular settling tank are: length 24 m, width 6 m and depth 3 m. If 2 hour detention period for tanks is recommended, the rate of flow of sewage per hour, is_____________________?

   A. 204 cu.m B. 208 cu.m C. 212 cu.m D. 216 cu.m...

8. In a city the ratio of the drainage to sewage is 20, the percentage discharge passing through non-monsoon periods, is_____________________?

   A. 5 B. 10 C. 15 D. 20...

9. A five day B.O.D. at 15°C of the sewage of a town is 100 kg/day. If the 5 day B.O.D. per head at 15°C for standard sewage is 0.1 kg/day, the population equivalent is____________________?

   A. 100 B. 1000 C. 5000 D. 10000...

10. If q is the average sewage flow from a city of population P, the maximum sewage flow______________?

    A. Q = [(4 + )/(18 + )] q B. Q = [(18 + P)/(4 + )] q C. Q = [(18 + )/(4 + )] q D. Q = [(5 + )/((15 + )] q...