Soda extract is useful when given mixture has any insoluble salt, it is prepared by:

Options

A. fusing soda and mixture and then extracting with water
B. dissolving `NaHCO_(3)` and mixture in dil. HCl
C. boiling `Na_(2)CO_(3)` and mixture in dil. HCl
D. boiling `Na_(2)CO_(3)` and mixture in distilled water

Answer

To prepare a soda extract when a given mixture contains any insoluble salt, follow these steps:

### Step-by-Step Solution:

1. **Gather Materials**: Collect the necessary materials, which include the insoluble salt, sodium carbonate (Na2CO3), and distilled water.

2. **Mix the Components**: Take the insoluble salt and mix it with sodium carbonate in a ratio of 1:2. For example, if you have 1 g of the insoluble salt, you should use about 2 g of sodium carbonate.

3. **Add Distilled Water**: Add a sufficient amount of distilled water to the mixture of sodium carbonate and the insoluble salt. The amount of water should be enough to allow for proper boiling and extraction.

4. **Boil the Mixture**: Heat the mixture on a hot plate or over a flame. Boil it for a certain period to ensure that the sodium carbonate reacts with the insoluble salt.

5. **Filter the Mixture**: After boiling, allow the mixture to cool slightly, then filter it to separate the solid residues from the liquid. The liquid that passes through the filter is known as the soda extract.

6. **Collect the Filtrate**: The filtrate obtained from the filtration process is your soda extract, which can be used for further qualitative analysis.

### Conclusion:
The soda extract is prepared by boiling the mixture of sodium carbonate and the insoluble salt in distilled water.