Lassaigne's test for the detection of nitrogen fails in

Options

A. `NH_(2)CONHNH_(2)*HCl`
B. `NH_(2)NH_(2)*HCl`
C. `NH_(2)CONH_(2)`
D. `C_(6)H_(5)NHNH_(2)*HCl`

Answer

**Step-by-Step Solution:**

1. **Understanding Lassaigne's Test:**
Lassaigne's test is a qualitative analysis method used to detect the presence of nitrogen in organic compounds. The test involves fusing the organic compound with sodium metal, followed by the addition of water to extract the sodium cyanide formed, which can then be tested for the presence of nitrogen.

2. **Analyzing the Given Options:**
We need to evaluate the options provided to determine which compound does not contain nitrogen that can be detected by Lassaigne's test.

3. **Identifying the Options:**
Let's denote the options as follows:
- Option 1: Contains carbon and nitrogen.
- Option 2: H2N, NH2HCl (Hydrazine hydrochloride)
- Option 3: Contains carbon and nitrogen.
- Option 4: Contains carbon and nitrogen.

4. **Evaluating Option 2:**
The compound H2N, NH2HCl (Hydrazine hydrochloride) does not contain any carbon atoms. Since Lassaigne's test requires the presence of carbon to form sodium cyanide, the absence of carbon means that the test cannot be performed.

5. **Conclusion:**
Therefore, Lassaigne's test for the detection of nitrogen fails in option 2 (H2N, NH2HCl).

**Final Answer:**
Lassaigne's test for the detection of nitrogen fails in option 2 (H2N, NH2HCl).

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