which one is soluble in NaOH :-

Options

A. N-Ethyl benzensulphonamide
B. N-N, di ethyl benzensulphonamide
C. N-ethyl aniline
D. N-methl ethanamine

Answer

To determine which compound is soluble in sodium hydroxide (NaOH), we need to analyze the given options based on their chemical structure and the presence of acidic protons.

### Step-by-Step Solution:

1. **Understanding Solubility in NaOH**:
- Sodium hydroxide is a strong base and can react with compounds that contain acidic protons. Compounds that can donate protons (H+) are generally soluble in NaOH.

2. **Analyzing the Options**:
- **Option A: N-ethylbenzene sulfonamide**: This compound has a sulfonamide group (–SO2NH) which can exhibit acidic behavior due to the presence of the nitrogen atom bonded to the sulfonyl group. This nitrogen can donate a proton, making it soluble in NaOH.
- **Option B: N-diethylbenzene sulfonamide**: Similar to option A, this compound also contains a sulfonamide group. It is likely to be soluble in NaOH as well.
- **Option C: N-ethyl aniline**: This compound is an amine and does not have an acidic proton that can react with NaOH, making it less likely to be soluble.
- **Option D: N-methyl ethanamine**: This is also an amine and lacks the acidic hydrogen that would allow it to be soluble in NaOH.

3. **Conclusion**:
- Among the options, both N-ethylbenzene sulfonamide and N-diethylbenzene sulfonamide are likely to be soluble in NaOH due to the presence of the sulfonamide group which can donate a proton. However, since the question asks for one, we can conclude that **N-ethylbenzene sulfonamide** is a clear choice as it is derived from a primary amine and is known to be soluble in NaOH.

### Final Answer:
**N-ethylbenzene sulfonamide is soluble in NaOH.**

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