Lactic acid on heating with conc. `H_(2)SO_(4)` gives

Options

A. Acetic acid
B. Propionic acid
C. Acrylic acid
D. Formic acid

Explanation

To solve the question regarding the reaction of lactic acid with concentrated sulfuric acid, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Lactic Acid**:
Lactic acid has the molecular formula \( \text{C}_3\text{H}_6\text{O}_3 \) and can be represented structurally as:
\[ \text{CH}_3\text{CH(OH)COOH} \]
It is an alpha-hydroxy acid.

2. **Understand the Role of Concentrated Sulfuric Acid**:
Concentrated sulfuric acid (\( \text{H}_2\text{SO}_4 \)) acts as a dehydrating agent. This means it will remove water from the lactic acid during the reaction.

3. **Dehydration Reaction**:
When lactic acid is heated with concentrated sulfuric acid, a dehydration reaction occurs. The hydroxyl group (-OH) from the lactic acid and a hydrogen atom (H) from the beta position (the carbon adjacent to the carbon bearing the carboxylic group) are removed, leading to the formation of a double bond.

4. **Formation of Acrylic Acid**:
The product of this dehydration reaction is acrylic acid, which has the structure:
\[ \text{CH}_2=\text{CHCOOH} \]
This compound is known as acrylic acid.

5. **Conclusion**:
Therefore, the final product of lactic acid when heated with concentrated sulfuric acid is acrylic acid.

### Final Answer:
The product formed when lactic acid is heated with concentrated sulfuric acid is **acrylic acid**.

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