Why sodium carbonate extract is used for testing acid radicals?

Explanation

### Step-by-Step Solution:

1. **Understanding the Role of Sodium Carbonate**: Sodium carbonate (Na2CO3) is a basic salt that can react with acids to form carbon dioxide gas and water. When sodium carbonate is added to a mixture containing various salts, it helps in dissolving the acid radicals (anions) present in the mixture.

2. **Preparation of Sodium Carbonate Extract**: To prepare the sodium carbonate extract, sodium carbonate is mixed with the sample containing the salts. This mixture is then treated with an acid (like HCl, HNO3, or H2SO4). The reaction leads to the formation of soluble salts and releases carbon dioxide gas, which helps in bringing the anions into solution.

3. **Separation of Acid and Basic Radicals**: One of the significant advantages of using sodium carbonate extract is that it helps in separating the basic radicals (cations) from the acidic radicals (anions). The basic radicals are usually colored and can interfere with the tests for acid radicals. By using sodium carbonate, these basic radicals can be removed, allowing for a clearer analysis of the acid radicals.

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