Reactant `overset(H_(3)O^(+))rarr CH_(3)COOH+HCl`

Answer

To solve the question regarding the reactant that undergoes hydrolysis to yield acetic acid (CH₃COOH) and hydrochloric acid (HCl), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Products**: The products given are acetic acid (CH₃COOH) and hydrochloric acid (HCl).

2. **Determine the Structure of the Reactant**: Since acetic acid has two carbon atoms, the reactant must also have two carbon atoms. The presence of HCl as a product suggests that the reactant is likely an acid chloride.

3. **Propose the Reactant**: The most plausible reactant that fits this description is acetyl chloride, which has the formula CH₃C(=O)Cl. This compound is an acid chloride and contains two carbon atoms.

4. **Write the Hydrolysis Reaction**: The hydrolysis of acetyl chloride can be represented as:
\[ \text{CH}_3C(=O)Cl + H_2O \xrightarrow{H_3O^+} \text{CH}_3COOH + HCl \]

5. **Mechanism of Hydrolysis**:
- **Step 1**: The water molecule attacks the carbonyl carbon of acetyl chloride, leading to the formation of a tetrahedral intermediate.
- **Step 2**: The chloride ion (Cl⁻) is expelled, resulting in the formation of acetic acid (CH₃COOH).
- **Step 3**: The proton (H⁺) from the water molecule combines with the chloride ion to form HCl.

6. **Final Confirmation**: The final products of this reaction are indeed acetic acid and hydrochloric acid, confirming that the reactant is correctly identified as acetyl chloride.

### Final Answer:
The reactant that undergoes hydrolysis to form CH₃COOH and HCl is **acetyl chloride (CH₃C(=O)Cl)**.

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