In permutit process, what is the role of the addition of the concentrated solution of the solidcompound obtained due to the reaction between NaOH with HCl? Explain.

In permutit process, what is the role of the addition of the concentra

1.	In permutit process, what is the role of the addition of the concentrated solution of the solidcompound obtained due to the reaction between NaOH with HCl? Explain.
Answer» SOLUTION :In permutit process, we use sodium permutit that is., `Na_(2)Al_(2)Si_(2)O_(8).x H_(2)O`. When hard water is treated with sodium premutit, Ca and Mg ions are EXCHANGE with the Na ions present in the permutit. After long use, most of the sodium ions present in permutit are REPLACED with calcium and magnesium ions and HENCE it becomes ineffective. Sodium hydroxide reacts with Hcl to from sodium chloride Concentrated sodium chloride solution is added to regenerate the permutit.