The compound that does not give a blue color in Lassaigne's test is

Options

A. `C_(6)H_(5) - NH_(2)`
B. `CH_(3)CONH_(2)`
C. `NH_(2) - NH_(2)`
D. `C_(6)H_(5) - NO_(2)`

Explanation

To solve the question regarding which compound does not give a blue color in Lassaigne's test, we can follow these steps:

### Step 1: Understand Lassaigne's Test
Lassaigne's test is a qualitative analysis technique used to detect the presence of nitrogen in organic compounds. When a compound containing nitrogen is heated with sodium metal, it forms sodium cyanide, which can then react with copper(II) sulfate to produce a blue color, indicating the presence of nitrogen.

### Step 2: Identify the Compounds
The compounds given in the question are:
1. C6H5NH2 (Aniline)
2. CH3CONH2 (Acetamide)
3. NH2C6H5 (Phenylamine)
4. C6H5NO2 (Nitrobenzene)

### Step 3: Analyze Each Compound
- **C6H5NH2 (Aniline)**: Contains carbon and nitrogen. It will give a blue color in Lassaigne's test.
- **CH3CONH2 (Acetamide)**: Contains carbon and nitrogen. It will also give a blue color in Lassaigne's test.
- **NH2C6H5 (Phenylamine)**: Contains carbon and nitrogen. It will give a blue color in Lassaigne's test.
- **C6H5NO2 (Nitrobenzene)**: Contains carbon and nitrogen. It will give a blue color in Lassaigne's test.

### Step 4: Identify the Compound Without Carbon
From the analysis, we see that all the compounds listed contain carbon. However, if the question had included a compound that does not contain carbon (like a simple amine such as NH3), that would not give a blue color in Lassaigne's test.

### Conclusion
Since all the given options contain carbon and nitrogen, we can conclude that none of the provided options fit the criteria of not giving a blue color in Lassaigne's test. However, if we were to consider a hypothetical compound without carbon, it would not yield a blue color.

### Final Answer
The compound that does not give a blue color in Lassaigne's test is not present among the options provided. However, if we consider a compound without carbon, such as NH3, it would not give a blue color.