Soda extract or sodium carbonate extract is prepared for

Options

A. testing all cations
B. testing all anions
C. testing anion which are water insoluble
D. all are correct

Explanation

To solve the question regarding the purpose of preparing a soda extract or sodium carbonate extract, we can follow these steps:

### Step 1: Understand the Composition of Soda Extract
Soda extract is prepared using sodium carbonate (Na2CO3). This compound is known for its alkaline properties and is commonly used in qualitative analysis.

### Step 2: Identify the Purpose of Soda Extract
The primary purpose of preparing a soda extract is to test for the presence of certain anions that are insoluble in water. This is because sodium carbonate can help to dissolve certain compounds, allowing for the identification of specific anions.

### Step 3: Evaluate the Options
1. **Tasting all cations** - This is incorrect because sodium carbonate does not specifically test for cations.
2. **Tasting all anions** - This is also incorrect as sodium carbonate is not used to test all anions.
3. **Testing for anions which are insoluble in water** - This is the correct option, as sodium carbonate is particularly useful for identifying anions that do not dissolve in water.

### Conclusion
The correct answer is that soda extract or sodium carbonate extract is prepared for testing anions which are insoluble in water.

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