Hard water contains salts of calcium and magnesium principally as bicarbonates, chlorides, and sulfates. Ferrous ion may also be present;
Explanation:
- Hard water contains salts of calcium and magnesium principally as bicarbonates, chlorides, and sulfates. Ferrous ion may also be present; oxidized to the ferric form. It appears as a reddish brown stain on washed fabrics and enameled surfaces.
- Water hardness that is caused by calcium bicarbonates is known as temporary, because boiling converts the bicarbonates to the insoluble carbonates; hardness from other salts is called permanent.
- Calcium and magnesium ions in hard water react with the higher fatty acids off soap to form an insoluble gelatinous curd, thereby causing a waste of the soap.
