When actaldehyde is treated with hydroxylamine, the medium should be:

Options

A. Highly basic
B. Highly acidic
C. Moderately acidic
D. None of the above

Answer

To determine the appropriate medium for the reaction between acetaldehyde and hydroxylamine, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- Acetaldehyde (CH3CHO) is an aldehyde that will react with hydroxylamine (NH2OH).

2. **Understand the Reaction Mechanism**:
- When acetaldehyde is treated with hydroxylamine, the nitrogen in hydroxylamine attacks the electrophilic carbon in the carbonyl group of acetaldehyde. This leads to the formation of a tetrahedral intermediate.

3. **Formation of the Intermediate**:
- The reaction begins with the nucleophilic attack of the nitrogen on the carbonyl carbon, which results in the formation of an intermediate that contains both hydroxylamine and the aldehyde.

4. **Proton Transfer**:
- In the intermediate, there is a possibility of proton transfer. A hydrogen atom from the hydroxyl group can shift to the nitrogen, stabilizing the intermediate.

5. **Equilibrium Consideration**:
- The reaction is in equilibrium, meaning that the intermediate can revert back to the starting materials (acetaldehyde and hydroxylamine). To drive the reaction towards the product, we need to stabilize the intermediate.

6. **Role of Acidic Medium**:
- Adding H+ ions (protons) to the reaction mixture will help stabilize the intermediate by forming an oxonium ion. This is crucial for the conversion of the intermediate to the final product, which is an oxime.

7. **Avoiding Strong Acidity**:
- A strongly acidic medium could lead to the formation of salts and may inhibit the reaction. Therefore, a moderately acidic medium is preferred, typically with a pH between 3 to 4.

8. **Conclusion**:
- The medium for the reaction between acetaldehyde and hydroxylamine should be moderately acidic to facilitate the formation of the oxime without leading to side reactions.

### Final Answer:
The medium should be moderately acidic.

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