Acetaldehyde on reaction with sodium hydrogen sulphite produces

Options

A.
B.
C.
D.

Answer

To solve the question regarding the reaction of acetaldehyde with sodium hydrogen sulfite, we will follow these steps:

### Step 1: Identify the Reactants
The reactants in this reaction are acetaldehyde (CH₃CHO) and sodium hydrogen sulfite (NaHSO₃).

### Step 2: Understand the Structure of Acetaldehyde
Acetaldehyde has the structure:
```
H
|
H--C=O
|
H
```
In this structure, the carbonyl carbon (C=O) is electrophilic due to the partial positive charge on the carbon atom.

### Step 3: Structure of Sodium Hydrogen Sulfite
Sodium hydrogen sulfite can be represented as:
```
O
||
Na-S-OH
```
Here, the sulfur atom has a partial positive charge and can act as a nucleophile.

### Step 4: Nucleophilic Attack
The nucleophilic sulfur atom from sodium hydrogen sulfite attacks the electrophilic carbon atom of the carbonyl group in acetaldehyde. This leads to the formation of a tetrahedral intermediate.

### Step 5: Formation of the Sulfonate Product
The reaction proceeds, and we get a sulfonate product. The structure of the product can be represented as:
```
H
|
H--C--O-SO₃Na
|
H
```
This product is known as the sodium bisulfite addition compound of acetaldehyde.

### Step 6: Final Product
The final product formed when acetaldehyde reacts with sodium hydrogen sulfite is:
- Sodium bisulfite adduct of acetaldehyde, which can be represented as CH₃CH(OSO₃Na)OH.

### Conclusion
The correct answer to the question is that acetaldehyde reacts with sodium hydrogen sulfite to produce the sodium bisulfite adduct.

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