200 Best MCQs on Water Treatment- biochemical engineering
Q9). Temporary hardness of water is caused by the presence of
a).chlorides of calcium and magnesium
b).sulfates of calcium and magnesium
c).bicarbonates of calcium and magnesium
d).carbonates of sodium and potassium
Correct Answer:
bicarbonates of calcium and magnesium
Explaination:
Q10). Secondary treatment uses __________ to consume wastes.
a).micro-organisms
b).chemicals
c).filtration
d).none of these
Correct Answer:
micro-organisms
Explaination:
Q11). Application of quaternary ammonium compounds as sanitizing agents tends to
a).favor gram positive bacteria
b).decrease gram positive bacteria
c).increase the percentage of gram(-)ve rods on utensils
d).none of the above
Correct Answer:
increase the percentage of gram(-)ve rods on utensils
Explaination:
Q12). Permanent hardness of water is caused by the presence of
a).bicarbonates of calcium and magnesium
b).carbonates of sodium and potassium
c).chlorides and sulfates of calcium and magnesium
d).phosphates of sodium and potassium
Correct Answer:
chlorides and sulfates of calcium and magnesium
Explaination:
Q13). According to BIS the maximum permissible limit of dissolved solids in drinking water is
a).1000 mg/l
b).500 mg/l
c).2000 mg/l
d).1500 mg/l
Correct Answer:
2000 mg/l
Explaination:
Q14). Acid used mostly for removal of milk stone is
a).phosphoric acid
b).nitric acid
c).gluconic acid
d).tartaric acid
Correct Answer:
nitric acid
Explaination:
Q15). Which of the following chemical is sometime added in the process of coagulation and flocculation?
a).Aluminum sulphate
b).Aluminum oxide
c).Calcium chloride
d).None of these
Correct Answer:
Aluminum sulphate
Explaination:
Q16). Which of the following physical method is used as germicidal in modern time for the treatment of drinking water?
a).Chlorination
b).Treating with potassium permagnate
c).UV radiation
d).Treating with bleaching powder
Correct Answer:
UV radiation
Explaination: