Water and its Treatment

Complete the following sentence "Hard water is water that

• forms a lather easily with water.

• does not form a lather easily with water

Which of the following compounds are responsible for causing temporary hardness in water?

• CaCl₂

• Ca(HCO₃₎₂

• CaSO₄

• Mg(HCO₃)₂

_________ hardness can be removed by boiling while __________ hardness cannot by removed by boiling.

Hardness of Water always has to be expressed in terms of

• CaSO4 equivalents

• CaCl2 Equivalent

• CaCO3 equivalents

• All of the above

-----------is the pH required in the determination of Hardness of water by EDTA method

• 4 to 6

• 9 to 14

• 8 to 10

• 1 to 4

1 ppm is eual to ------------ ⁰Clark

One ⁰ French is equal to ----------ppm

-------------is the indicator used in EDTA method

• EAR

• EBT

• ESR

• Methyl Orange

Abbreviate EDTA-----------

Chlorides and Sulphates causes -------------type of hardness

• Temporary Hardness

• Permanent Hardness