Hardness of water is caused by_____.

turbidity

presence of soap lather

presence of chlorides and sulphates of sodium and potassium

presence of bicarbonates, sulphates or chlorides of calcium and magnesium

Correct Answer : presence of bicarbonates, sulphates or chlorides of calcium and magnesium

Recently Updated in Water Supply Engineering Questions

Normal values of overflow rate for plain sedimentation tanks in litres/hr/m², generally range between

100 to 250

250 to 500

500 to 750

750 to 1000

Correct Answer : Option (C) : 500 to 750

When gravity and pumping systems of water distribution are adopted, the type of distribution reservoir, is____.

intz tank

elevated tank

stand pipe

ground source reservoir

Correct Answer : Option (B) : elevated tank

If n is porosity, y is specific yield and r is specific retention of any soil, the relationship which holds good, is_____.

n + y = r

y + r = n

n + r + y = 0

n + y + r = 1

Correct Answer : Option (B) : y + r = n