In the given reaction `CH_(3)CH_(2) CH = CHCH_(3) overset(X) to CH_(3)CH_(2)COOH +`
`CH_(3)COOH`
The X is

Options

A. `C_(2)H_(5)ON a`
B. Conc. `HCl + "Anhy"ZnCl_(2)`
C. Anh. `AlCl_(3)`
D. `KMnO_(4)//OH^(-)`

Explanation

To solve the given reaction and identify the reagent \( X \), we will follow these steps:

### Step 1: Identify the Reactant
The reactant is \( CH_3CH_2CH=CHCH_3 \), which is 2-pentene. This compound has a double bond between the second and third carbon atoms.

### Step 2: Understand the Reaction
The reaction leads to the formation of two carboxylic acids: propanoic acid (\( CH_3CH_2COOH \)) and acetic acid (\( CH_3COOH \)). This indicates that the double bond in the alkene is undergoing oxidative cleavage.

### Step 3: Determine the Type of Reaction
The reaction is an oxidative cleavage of the double bond. This type of reaction typically requires an oxidizing agent.

### Step 4: Identify Possible Reagents
We need to identify which reagent can facilitate oxidative cleavage. The options provided are:
1. Sodium ethoxide
2. Concentrated HCl + Anhydrous zinc chloride
3. Anhydrous aluminum chloride
4. Potassium permanganate (\( KMnO_4 \)) in the presence of hydroxide ions (\( OH^- \))

### Step 5: Analyze the Options
- **Sodium ethoxide**: This acts as a base and does not facilitate oxidative cleavage.
- **Concentrated HCl + Anhydrous zinc chloride**: This is a reagent used for different purposes, not for oxidative cleavage.
- **Anhydrous aluminum chloride**: This is a Lewis acid and is not suitable for oxidative cleavage.
- **Potassium permanganate (\( KMnO_4 \))**: This is a well-known oxidizing agent that can cleave double bonds oxidatively.

### Step 6: Confirm the Correct Reagent
Using \( KMnO_4 \) in the presence of \( OH^- \) will lead to the formation of aldehydes first, followed by further oxidation to carboxylic acids. The reaction proceeds as follows:
1. The double bond is cleaved to form aldehydes.
2. The aldehydes are then oxidized to form the corresponding carboxylic acids.

### Conclusion
Thus, the reagent \( X \) that facilitates the oxidative cleavage of the double bond in 2-pentene to yield propanoic acid and acetic acid is \( KMnO_4 \) in the presence of \( OH^- \).

### Final Answer
The reagent \( X \) is \( KMnO_4 \) in \( OH^- \).

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