Question

The name of the salt used to remove permanent hardness of water is ______.

Options

• Sodium hydrogen carbonate (NaHCO₃) 

• Sodium chloride (NaCl) 

• Sodium carbonate decahydrate (Na₂CO₃.10H₂O)

• Calcium sulphate hemihydrate (CaSO₄.`1/2`H₂O)

Answer 1

The name of the salt used to remove permanent hardness of water is Sodium carbonate decahydrate (Na₂CO₃.10H₂O).

Explanation:

Insoluble carbonates are created when washing soda reacts with the salts in water and are easily removed through physical means.