In the reaction sequence
`C_2H_5Cl+KCNoverset(C_2H_5OH)rarrX`
What is the molecular formula of X is

Options

A. `C_2H_5CN`
B. `C_2H_5NC`
C. `C_2H_5OH`
D. `C_2H_6O`

Explanation

To determine the molecular formula of the product \( X \) in the reaction sequence:

\[ C_2H_5Cl + KCN \overset{(C_2H_5OH)}{\rightarrow} X \]

we will analyze the reaction step by step.

### Step 1: Identify the Reactants
The reactants are:
- Ethyl chloride (\( C_2H_5Cl \))
- Potassium cyanide (\( KCN \))
- Ethanol (\( C_2H_5OH \)) as a solvent

### Step 2: Understand the Role of the Nucleophile
In this reaction, the cyanide ion (\( CN^- \)) from potassium cyanide acts as a nucleophile. The \( CN^- \) ion will attack the electrophilic carbon in ethyl chloride.

### Step 3: Nucleophilic Substitution Reaction
The nucleophilic substitution occurs as follows:
- The \( CN^- \) ion attacks the carbon atom that is bonded to the chlorine atom in \( C_2H_5Cl \).
- This results in the displacement of the chlorine atom, which leaves as a chloride ion (\( Cl^- \)).

### Step 4: Formation of the Product
The product formed from this reaction is ethyl cyanide (or propionitrile), which has the molecular formula:
\[ C_2H_5CN \]

### Step 5: Write the Molecular Formula of Product \( X \)
The molecular formula of \( X \) is:
\[ C_2H_5CN \]

### Conclusion
Thus, the molecular formula of \( X \) is \( C_2H_5CN \).

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