The formula for permutit or zeolite which is used as softner in ion - exchange method is

Options

A. `NaAlSiO_(4)`
B. `NaAlO_(2)`
C. `Ca_(3)(PO_(4))_(2)`
D. `Na_(2)SO_(4)`

Explanation

To find the formula for permutit or zeolite, which is used as a softener in the ion-exchange method, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Context**:
- Permutit or zeolite is a material used in water softening processes. It works by exchanging calcium and magnesium ions found in hard water with sodium ions.

2. **Identifying the Chemical Formula**:
- The general formula for zeolite is given as Na2Al2Si2O8·xH2O, where "x" represents the number of water molecules associated with the compound.

3. **Simplifying the Formula**:
- We can simplify the formula by factoring out common elements. If we take 2 as a common factor from Na2Al2Si2O8, we can rewrite it as:
\[ Na2Al2Si2O8 = 2 \times NaAlSiO4 \]
- This shows that the basic unit of zeolite can be represented as NaAlSiO4.

4. **Finalizing the Answer**:
- Therefore, the formula for permutit or zeolite used as a water softener can be expressed as NaAlSiO4.

### Conclusion:
The formula for permutit or zeolite, which is used as a softener in the ion-exchange method, is NaAlSiO4.

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