Water Treatment MCQs

Question 1

The maximum desirable limit Bureau of Indian Standards (BIS) of lead in the drinking water is

Accepted Answer

0.05 mg/l

Answer

0.09 mg/l

Answer

0.1 mg/l

Answer

1.0 mg/l

Question 2

Zeolite softening process removes

Accepted Answer

both temporary and permanent hardness of water

Answer

only temporary hardness of water

Answer

only permanent hardness of water

Answer

the dissolved gases in permanent hard water

Question 3

Conventional tertiary treatment is

Accepted Answer

chemical coagulation and flocculation

Answer

filtration

Answer

sedimentation

Answer

none of these

Question 4

The maximum desirable limit (BIS) of total hardness (as CaCo3) in drinking water is

Accepted Answer

300 ppm

Answer

600 ppm

Answer

500 ppm

Answer

1000 ppm

Question 5

The chemical oxygen demand (COD)measures the

Accepted Answer

amount of oxygen that would be removed from the water in order to oxidize pollution

Answer

amount of oxygen required for growth of microorganisms in water

Answer

amount of oxygen required to oxidize the calcium present in waste water

Answer

none of the above

Question 6

Hardness of water does not

Accepted Answer

make it unfit for drinking

Answer

have any bad effect in boiler

Answer

make cooking of foods difficult

Answer

cause difficulty in the washing of clothes with soaps

Question 7

Permanent hard water may be softened by passing it through

Accepted Answer

sodium hexametaphosphate

Answer

sodium silicate

Answer

sodium bicarbonate

Answer

sodium phosphate

Question 8

Zeolite used in zeolite softening process for the treatment of hard water gets exhausted after certain time of usage but can be regenerated by flushing it with

Accepted Answer

10% sodium chloride solution

Answer

10% calcium chloride solution

Answer

10% magnesium sulfate solution

Answer

10% magnesium chloride solution

Question 9

Temporary hardness of water is caused by the presence of

Accepted Answer

bicarbonates of calcium and magnesium

Answer

chlorides of calcium and magnesium

Answer

sulfates of calcium and magnesium

Answer

carbonates of sodium and potassium