Note: In the following questions a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices.
Assertion : Lassaigne's test is not shown by diazonium salts.
Reason : Diazonium salts lose `N_2` on heating much before than they have a chance to react with fused sodium.

Answer

To solve the assertion and reason question, we will analyze both the assertion and the reason step by step.

### Step 1: Understand the Assertion
The assertion states: "Lassaigne's test is not shown by diazonium salts."

**Explanation**: Lassaigne's test is a qualitative analysis method used to detect the presence of certain elements (like nitrogen, sulfur, and halogens) in organic compounds. However, diazonium salts do not give a positive result in this test.

### Step 2: Understand the Reason
The reason states: "Diazonium salts lose N2 on heating much before they have a chance to react with fused sodium."

**Explanation**: When diazonium salts are heated, they decompose readily to release nitrogen gas (N2). This decomposition occurs quickly, preventing the diazonium salts from reacting with the sodium in Lassaigne's test. Thus, the nitrogen that would be detected in the test is lost as gas before the test can be conducted.

### Step 3: Conclusion
Both the assertion and the reason are correct. The assertion is true because diazonium salts do not show Lassaigne's test due to their tendency to lose nitrogen gas upon heating. The reason is also true, as it accurately explains why diazonium salts do not participate in Lassaigne's test.

### Final Answer
Both the assertion and reason are true statements, and the reason is the correct explanation for the assertion.

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