Question
Download Solution PDFPermanent hardness of water cannot be removed by which one of the following methods?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe presence of chlorides and sulphates of Magnesium and Calcium ions leads to the permanent hardness of water.
- Washing Soda or Sodium carbonate (Na2CO3), can soften water that has temporary hardness. It can also help in treating the permanent hardness of water.
- Calgon’s Method - In this method, adding Calgon to hard water causes the displacement of calcium and magnesium ions with sodium ions from the Calgon anion. This, thus results in the removal of calcium and magnesium ions from hard water.
- In the Ion Exchange method, one or more undesirable ions get displaced with another less objectionable ionic substance.
- Boiling will instead lead to evaporation of water leaving undissolved salts. Hence, it won’t remove the hardness of water.
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