Hardness of water is contributed by following salts except-
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. ii)Permanent (Non-Carbonate) hardness --> Calcium Sulfate, magnesium sulfate, Calcium chloride, magnesium chloride. It is called permanent because it cannot be removed by boiling.
Calcium gluconate
Magnesium chloride
Calcium sulfate
Magnisum bicarbonate