What is X in the following reaction ?
`C_2H_5Cl+XrarrC_2H_5OH+KCl`

Options

A. `KHCO_3`
B. alc. `KOH`
C. aq. `KOH`
D. `K_2CO_3`

Explanation

To determine what X is in the reaction:

\[ C_2H_5Cl + X \rightarrow C_2H_5OH + KCl \]

we can analyze the reaction step by step.

### Step 1: Identify the Reaction Type
The reaction involves the conversion of ethyl chloride (C₂H₅Cl) to ethyl alcohol (C₂H₅OH) and potassium chloride (KCl). This indicates that a nucleophilic substitution reaction is taking place, where the chlorine atom (Cl) is being replaced by a hydroxyl group (OH).

**Hint:** Look for the type of reaction happening (substitution vs. elimination).

### Step 2: Determine the Role of X
In this reaction, X must be a nucleophile that can provide the hydroxyl group (OH) to replace the chlorine atom. The presence of KCl as a product suggests that X must also be a source of potassium ions (K⁺) and hydroxide ions (OH⁻).

**Hint:** Consider common nucleophiles that can provide OH⁻ in an aqueous solution.

### Step 3: Identify X
The most common source of hydroxide ions in an aqueous solution is potassium hydroxide (KOH). When KOH is dissolved in water, it dissociates into K⁺ and OH⁻ ions. Therefore, in this reaction, X is KOH.

**Hint:** Think about strong bases that can dissociate in water to give OH⁻ ions.

### Step 4: Write the Final Reaction
Now we can rewrite the reaction with X identified as KOH:

\[ C_2H_5Cl + KOH \rightarrow C_2H_5OH + KCl \]

This confirms that the chlorine atom in ethyl chloride is replaced by the hydroxyl group from KOH, resulting in the formation of ethyl alcohol and potassium chloride.

**Hint:** Ensure that the products of the reaction are balanced and correctly represent the reactants.

### Conclusion
Thus, the value of X in the reaction is:

**X = KOH**

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