Chloroacetic acid is a stronger acid than acetic acid this can be explained using

Options

A. `-M- effect`
B. `-l- effect`
C. `+M-effect`
D. `+l-effect`

Answer

To explain why chloroacetic acid is a stronger acid than acetic acid, we can analyze the structural and electronic differences between the two compounds.

### Step-by-Step Solution:

1. **Identify the Structures**:
- Chloroacetic acid (ClCH2COOH) consists of a chloro group (Cl) attached to the carbon adjacent to the carboxylic acid group (-COOH).
- Acetic acid (CH3COOH) has a methyl group (CH3) attached to the same carbon.

2. **Understand Acid Strength**:
- The strength of an acid is determined by the stability of its conjugate base after the acidic hydrogen (H+) is released.
- The more stable the conjugate base, the stronger the acid.

3. **Conjugate Bases**:
- When acetic acid donates a proton (H+), it forms the acetate ion (CH3COO-).
- When chloroacetic acid donates a proton, it forms the chloroacetate ion (ClCH2COO-).

4. **Analyze the Conjugate Bases**:
- The acetate ion has a methyl group (CH3), which is an electron-donating group (+I effect). This increases electron density on the conjugate base, making it less stable.
- The chloroacetate ion has a chloro group (Cl), which is an electron-withdrawing group (-I effect). This decreases electron density on the conjugate base, stabilizing it.

5. **Effect of Electron-Withdrawing Groups**:
- The presence of the chlorine atom in chloroacetic acid pulls electron density away from the carboxylate ion, increasing its stability compared to the acetate ion.
- The increased stability of the chloroacetate ion makes chloroacetic acid a stronger acid than acetic acid.

6. **Conclusion**:
- Therefore, the reason chloroacetic acid is a stronger acid than acetic acid is due to the -I effect of the chlorine atom, which stabilizes the conjugate base.

### Final Answer:
Chloroacetic acid is a stronger acid than acetic acid due to the -I effect of the chlorine atom, which stabilizes the conjugate base.

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