A. only carbonate hardness is removed
B. only non-carbonate hardness is re-moved
C. lime reduces the carbonate hardness and soda-ash removes the non-carbo¬nate hardness
D. lime reduces the non-carbonate hard-ness and soda-ash removes the carbo¬nate hardness
Related Mcqs:
- The major disadvantage of lime soda process of water softening is that_________________?
A. it is unsuitable for turbid and acidic water
B. huge amount of precipitate is formed which creates a disposal problem
C. the effluent cannot be reduced to zero hardness
D. it is unsuitable for softening the water of excessive hardness - 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 - 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 - The water carriage system of collection of waste product________________?
A. is cheaper in initial cost than dry conservancy system
B. requires treatment before disposal
C. creates hygenic problem
D. all of the above - The rate of BOD exerted at any time is_____________?
A. directly proportional to BOD satisfied
B. directly proportional to BOD remain-ing
C. inversely proportional to BOD satisfied
D. inversely proportional to BOD re-maining - When there is no recirculation of sewage, then recirculation factor is_______________?
A. 0
B. 1
C. infinity
D. none of the above - If Biochemical oxygen demand (BOD. of a town is 20000 kg/day and BOD per capita per day is 0.05 kg, then population equivalent of town is_________________?
A. 1000
B. 4000
C. 100000
D. 400000 - Hardy cross method of analysis of distribution system________________?
1) involves successive trials
2) takes economic aspects into account
3) is time consuming
The correct answer is?A. only (1)
B. (1)and(2)
C. (1) and (3)
D. all are correct - Air binding phenomena in rapid sand filters occur due to_________________?
A. excessive negative head
B. mud ball formation
C. higher turbidity in the effluent
D. low temperature - Ground water is usually free from________________?
A. suspended impurities
B. dissolved impurities
C. both suspended and dissolved impuri¬ties
D. none of the above
