Among the following the strongest acid is

Options

A. `CH_3COOH`
B. `C_6H_5COOH`
C. `m-CH_3OC_6H_4COOH`
D. `p-CH_3OC_6H_4COOH`

Explanation

To determine the strongest acid among the given options, we can follow these steps:

### Step 1: Identify the Acids
First, we need to identify the acids provided in the options. Typically, these may include a variety of carboxylic acids, both aliphatic and aromatic.

### Step 2: Understand Acid Strength
Acid strength can be influenced by several factors, including:
- The presence of electron-withdrawing groups (which increase acidity).
- The presence of electron-donating groups (which decrease acidity).
- The structure of the acid (aromatic vs. aliphatic).

### Step 3: Compare Aliphatic and Aromatic Acids
- Aliphatic acids (like acetic acid) tend to be weaker than aromatic acids (like benzoic acid) because the alkyl groups exert a positive inductive effect, which destabilizes the carboxylate ion formed after deprotonation.
- Aromatic acids have a more stable carboxylate ion due to resonance stabilization.

### Step 4: Analyze Substituted Aromatic Acids
When comparing substituted aromatic acids:
- Electron-donating groups (like -CH3 or -OCH3) decrease acidity due to their +I effect.
- Electron-withdrawing groups (like -NO2) increase acidity.

### Step 5: Conclusion
Based on the above analysis, we conclude that:
- Unsubstituted benzoic acid is stronger than aliphatic acids.
- Substituted benzoic acids with electron-donating groups are weaker than unsubstituted benzoic acid.

Thus, the strongest acid among the options is likely to be benzoic acid or an unsubstituted aromatic acid.

### Final Answer
The strongest acid among the following is **Benzoic Acid**.

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