A. 60 mg/litre
B. 75 mg/litre
C. 100 gm/litre
D. 150 mg/litre
Related Mcqs:
- By boiling water, hardness can be removed if it is due to_________________?
A. calcium sulphate
B. magnesium sulphate
C. calcium nitrate
D. calcium bicarbonate
E. none of these - The yield of a rapid gravity filter as compared to that of slow sand filter, is__________________?
A. 10 times
B. 15 times
C. 20 times
D. 30 times
E. 35 times - The R.L. of ground water table on the sides of a valley is 1505 m whereas R.L. of the stream water is 1475 m. If 60° slope consists of pervious soil between R.L. 1485 m to 1500 m, the gravity spring may be expected at the point of reduced level_______________?
A. 1500 m
B. 1505 m
C. 1475 m
D. 1485 m - Disinfection of drinking water, is done to remove_________________?
A. odour
B. bacterias
C. turbidity
D. colour - The underground sources of water, is from______________?
Pick up the incorrect statement from the following?
A. wells
B. springs
C. infiltration wells
D. storage reservoirs
E. none of these - For determining the velocity of flow of underground water, the most commonly used non-empirical formula is________________?
A. Darcy’s formula
B. Slichter’s formula
C. Hazen’s formula
D. Lacy’s formula - Acidity in water is caused due to_______________?
A. Mineral acids
B. Free CO2
C. Iron sulphate
D. Aluminium sulphate
E. All the above - Biochemical Oxygen Demand (B.O.D.) of safe drinking water must be________________?
A. nil
B. 5
C. 10
D. 15
E. 20 - Aeration of water is done to remove______________?
A. odour
B. colour
C. bacterias
D. hardness
E. turbidity - If four fires break out in a city of population 40 lakhs and if each hydrant has three streams and duration of each fire is four hours, the total quantity of water required, is______________________?
A. 1880 kilo litres
B. 2880 kilo litres
C. 3880 kilo litres
D. 4880 kilo litres
