A. 2 to 4
B. 4 to 6
C. 6 to 8
D. 8 to 10
Related Mcqs:
- The alum, when added as a coagulant in water_______________?
A. does not require alkalinity in water for flocculation
B. does not affect pH value of water
C. increases pH value of water
D. decreases pH value of water - The amount of coagulant needed for coagulation of water increases with_______________?
1) increase in turbidity of water
2) decrease in turbidity of water
3) increase in temperature of water
4) decrease in temperature of water
The correct answer is?A. (1) and (2)
B. (1)and (4)
C. (2) and (3)
D. (2) and (4) - The maximum permissible limit for flouride in drinking water is______________?
A. 0.1 mg/litre
B. 1.5 mg/litre
C. 5 mg/litre
D. 10 mg/litre - Average rate of water consumption perhead per day as per Indian Standard is______________?
A. 100 litres
B. 135 litres
C. 165 litres
D. 200 litres - The minimum dissolved oxygen which should always be present in water in order to save the aquatic life is______________?
A. 1 ppm
B. 4 ppm
C. 10 ppm
D. 40 ppm - The effective size of sand particles used in slow sand filters is_______________?
A. 0.25 to 0.35 mm
B. 0.35 to 0.60 mm
C. 0.60 to 1.00 mm
D. 1.00 to 1.80 mm - Assertion A : The consumption of water increases with increase in the distribution pressure. Reason R : Higher distribution pressure causes more loss and waste of water. Select your answer according to the coding system given below?
A. Both A and R are true and R is the correct explanation of A
B. Both A and R are true but R is not the correct explanation of A
C. A is true but R is false
D. A is false but R is true - For satisfactory working of a sludge digestion unit, the pH range of digested sludge should be maintained as___________________?
A. 4.5 to 6.0
B. 6.5 to 8.0
C. 8.5 to 10.0
D. 10.5 to 12.0 - The relative stability of a sewage sample, whose dissolved oxygen is same as the total oxygen required to satisfy BOD, is______________?
A. 1
B. 100
C. infinite
D. zero - Dissolved oxygen in streams is______________?
A. maximum at noon
B. minimum at noon
C. maximum at midnight
D. same throughout the day
