The solution of a sample in a tube will be identified as a chloride if it gives
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Correct Answer: Option C
Explanation:
The correct answer is C: a white precipitate when acidified with dilute HNO₃ and then AgNO₃ solution added.
Here's why:
The identification of chloride ions (Cl⁻) is typically done by adding silver nitrate (AgNO₃) solution to an acidified solution. Chlorides react with silver nitrate to form a white precipitate of silver chloride (AgCl). However, to avoid interference from other ions (like carbonate or sulfite), the solution should first be acidified with dilute nitric acid (HNO₃). This ensures that no carbonate or sulfide ions are present, as these could also react with silver nitrate and form precipitates.
Thus, the reaction you're looking for is:
- Add dilute nitric acid (HNO₃) to remove carbonate or sulfide impurities.
- Add silver nitrate (AgNO₃), which will then form a white precipitate if chloride ions (Cl⁻) are present, forming AgCl.
So, option C is correct.
The correct answer is C: a white precipitate when acidified with dilute HNO₃ and then AgNO₃ solution added.
Here's why:
The identification of chloride ions (Cl⁻) is typically done by adding silver nitrate (AgNO₃) solution to an acidified solution. Chlorides react with silver nitrate to form a white precipitate of silver chloride (AgCl). However, to avoid interference from other ions (like carbonate or sulfite), the solution should first be acidified with dilute nitric acid (HNO₃). This ensures that no carbonate or sulfide ions are present, as these could also react with silver nitrate and form precipitates.
Thus, the reaction you're looking for is:
- Add dilute nitric acid (HNO₃) to remove carbonate or sulfide impurities.
- Add silver nitrate (AgNO₃), which will then form a white precipitate if chloride ions (Cl⁻) are present, forming AgCl.
So, option C is correct.