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Grade 12th passPhysical Chemistry

Permanent Hardness of water can be removed by adding
A) Bleaching powder
B) Chlorine
C) Wasshing soda
D) Potassium permanganate

Profile image of Harshit Singh
5 Years agoGrade 12th pass
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1 Answer

Profile image of Pawan Prajapati
5 Years ago
C) Wasshing soda
Explanation:
Hardness can be removed by adding sodium carbonate (washing soda) or by passing the water through an ion-exchange column.
Hardness in water is caused by dissolved magnesium ions and calcium ions. These can get into the water when it comes into contact with limestone and other rocks that contain calcium compounds. This can happen, for example, when rainwater flows over these rocks on its way to a reservoir