The acid formed when propyl magnesium bromide is treated with `CO_(2)` is -

Options

A. `CH_(3)CH_(2)COOH`
B. `C_(3)H_(7)COOH`
C. `CH_(3)CH_(2)CH_(2)CH_(2)COOH`
D. None

Answer

To determine the acid formed when propyl magnesium bromide is treated with carbon dioxide, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Grignard Reagent**:
Propyl magnesium bromide (C3H7MgBr) is a Grignard reagent. It consists of a propyl group (C3H7) bonded to a magnesium bromide (MgBr).

2. **Reaction with Carbon Dioxide**:
When the Grignard reagent reacts with carbon dioxide (CO2), the nucleophilic carbon of the propyl group attacks the electrophilic carbon of the carbon dioxide molecule. This results in the formation of a carboxylate intermediate.

\[ \text{C}_3\text{H}_7\text{MgBr} + \text{CO}_2 \rightarrow \text{C}_3\text{H}_7\text{COO}^- \text{MgBr}^+ \]

3. **Formation of Carboxylic Acid**:
The carboxylate ion (C3H7COO^-) can then undergo hydrolysis. In hydrolysis, water (H2O) reacts with the carboxylate ion to form the corresponding carboxylic acid.

\[ \text{C}_3\text{H}_7\text{COO}^- + \text{H}_2\text{O} \rightarrow \text{C}_3\text{H}_7\text{COOH} + \text{OH}^- \]

4. **Naming the Acid**:
The resulting carboxylic acid is propanoic acid (C3H7COOH), which is also known as propionic acid. It has three carbon atoms in the chain.

### Final Answer:
The acid formed when propyl magnesium bromide is treated with carbon dioxide is **propanoic acid (propionic acid)**.

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