Predict the product (B) in the following sequence of reactions:
`"Ethylbenzene" overset(KMnO_(4)-KOH)to A overset(H_(3)O^(+))to B`

Options

A. Benzaldehyde
B. Benzophenone
C. Benzene
D. Benzoic acid

Explanation

To predict the product (B) in the given sequence of reactions involving ethylbenzene, we will follow these steps:

### Step 1: Identify the starting compound
The starting compound is ethylbenzene, which has the structure:
- Ethyl group (C2H5) attached to a benzene ring (C6H5).

### Step 2: Understand the first reaction with KMnO4 and KOH
Ethylbenzene is treated with potassium permanganate (KMnO4) in the presence of potassium hydroxide (KOH). This is an oxidative reaction. KMnO4 is a strong oxidizing agent that can oxidize the ethyl group attached to the benzene ring.

### Step 3: Determine the oxidation product (A)
When ethylbenzene is oxidized by KMnO4, the ethyl group (C2H5) is converted into a carboxylic acid group (-COOH). The product (A) of this reaction is thus benzoic acid (C6H5COOH).

### Step 4: Understand the second reaction with H3O+
The product (A), which is benzoic acid, is then treated with H3O+ (hydronium ions). Since benzoic acid is already in its acid form, there is no further reaction that changes its structure.

### Step 5: Identify the final product (B)
Therefore, the final product (B) after the second reaction remains benzoic acid (C6H5COOH).

### Conclusion
The final product (B) of the given sequence of reactions is **benzoic acid**.

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