Addition of which compounds shall make water hard?
A. Chlorides of Calcium and Magnesium
B. Sulphates of Calcium and Magnesium
C. Carbonates of Calcium and Magnesium
A & C only
B & C only
A and B only
A, B and C
Hard water is the water that contains salts of calcium and magnesium such as bicarbonates, chlorides, and sulfates.