<prompt> Hardness of water is contributed by following salts except-Calcium gluconateMagnesium chlorideCalcium sulfateMagnisum bicarbonate  <response>: Ans. is a i.e., Calcium gluconate o I lardness may be : - i Temporary Carbonate hardness Calcium bicarbonate Magnesium bicarbonate. It is called temporary because it can be removed by boiling or addition of lime. iiPermanent Non-Carbonate hardness -- Calcium Sulfate, magnesium sulfate, Calcium chloride, magnesium chloride. It is called permanent because it cannot be removed by boiling. 