Explain why :
Presence of Cl in a compound cannot be detected by adding `AgNO_3` solution to sodium extract if the compound contains nitrogen also.

Explanation

To explain why the presence of chlorine in a compound cannot be detected by adding AgNO3 (silver nitrate) solution to sodium extract if the compound contains nitrogen, we can break down the reasoning into several steps:

### Step-by-Step Solution:

1. **Understanding the Components**: The compound in question contains both chlorine (Cl) and nitrogen (N). When we prepare a sodium extract from this compound, it will contain sodium salts of both chlorine and nitrogen.

2. **Formation of Sodium Extract**: When the compound is treated with sodium, it forms sodium chloride (NaCl) from chlorine and sodium cyanide (NaCN) from nitrogen. Thus, the sodium extract will contain both NaCl and NaCN.

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