In the reaction :
`CH_(3)CHCl_(2) overset("aq. KOH")to "Intermediate" to X`, X is :

Options

A. `CH_(3)CHO`
B. `(CH_(3))_(2)CO`
C. `CH_(3)CH_(2)OH`
D. `underset(OH)underset(|)CH_(2)-underset(OH)underset(|)CH_(2)`

Explanation

To solve the problem, we need to analyze the reaction step by step:

### Step 1: Identify the Reactant
The reactant given is CH₃CHCl₂, which is 1,1-dichloroethane.

### Step 2: Understand the Role of Aqueous KOH
Aqueous KOH acts as a nucleophile in this reaction. In this context, it will facilitate a nucleophilic substitution reaction where the chlorine atoms (Cl) will be replaced by hydroxyl groups (OH).

### Step 3: Nucleophilic Substitution Reaction
In the presence of aqueous KOH, the two chlorine atoms in CH₃CHCl₂ will be substituted by hydroxyl groups. This means that the reaction will proceed as follows:
- The first chlorine atom (Cl) is replaced by OH, resulting in CH₃CH(OH)Cl.
- The second chlorine atom (Cl) is then replaced by another OH, leading to CH₃C(OH)(OH).

### Step 4: Formation of the Intermediate
The intermediate formed after both substitutions is CH₃C(OH)₂. This compound has two hydroxyl groups on the same carbon, which is not stable.

### Step 5: Elimination of Water
To stabilize the intermediate, a water molecule is eliminated. This can occur by taking one hydroxyl group (OH) and one hydrogen atom (H) from the adjacent carbon, resulting in the formation of a double bond.

### Step 6: Final Product (X)
After the elimination of water, the final product (X) is formed, which is CH₃CH=O. This compound is an aldehyde known as acetaldehyde.

### Conclusion
Thus, the product X formed from the reaction of CH₃CHCl₂ with aqueous KOH is acetaldehyde (CH₃CHO).

### Answer
X is CH₃CHO (acetaldehyde).

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