Permanent hardness of water is caused by -
Chloride of Mg and Ca
Bicarbonates of Na and K
Sulphates of Mg and Ca
Both 1 and 3
Hard water is the water that contains salts of calcium and magnesium such as bicarbonates, chlorides, and sulfates. Water hardness caused by bicarbonates is known as temporary hardness. Hardness due to presence of the chlorides and sulfates salts is permanent hardness.