The compound formed as a result of oxidation of ethyl benzene by `KMnO_(4)` is:

Options

A. benzophenone
B. acetophenone
C. benzoic acid
D. benzyl alcohol

Explanation

To solve the question regarding the oxidation of ethyl benzene by KMnO4, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure of Ethyl Benzene**:
Ethyl benzene consists of a benzene ring with an ethyl group (C2H5) attached to it. The structural formula can be represented as:
\[ C_6H_5-CH_2-CH_3 \]

2. **Understand the Oxidation Process**:
KMnO4 is a strong oxidizing agent. When ethyl benzene is oxidized, the ethyl group can be oxidized to a carboxylic acid. The oxidation typically involves the removal of hydrogen atoms and the addition of oxygen.

3. **Oxidation Mechanism**:
- During the oxidation, the ethyl group (–CH2–CH3) is oxidized to a carboxylic acid (–COOH).
- The hydrogen atoms from the ethyl group are removed, and hydroxyl (–OH) groups are added in the process.

4. **Formation of Benzoic Acid**:
- The final product after complete oxidation of ethyl benzene is benzoic acid (C6H5COOH).
- The reaction can be summarized as:
\[ C_6H_5-CH_2-CH_3 \xrightarrow{KMnO_4} C_6H_5-COOH \]

5. **Conclusion**:
The compound formed as a result of the oxidation of ethyl benzene by KMnO4 is **benzoic acid**.

### Final Answer:
The compound formed as a result of oxidation of ethyl benzene by KMnO4 is **benzoic acid (C6H5COOH)**.

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