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- When hard water is passed through sodium permutit, sodium ions are replaced with Ca2+ and Mg2+ making water soft
since ions responsible for water hardness have been removed.
OR
Ion-exchange process:
- Hard water is passed through a column filled with a complex sodium compound (sodium permuttit) / ion exchanger;
- The Ca2+ and Mg2+ ions in the hard water are precipitated and remains in the column while the sodium ions from the column comes out with the water hence becoming soft.
john3 answered the question on November 3, 2017 at 07:52
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