Assertion : Alkyl isocyanides in acidified water give alkyl formamides.
Reason : In isocyanides, carbon first act as a nucleophile and then as electrophile.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Analyze the Assertion
**Assertion:** Alkyl isocyanides in acidified water give alkyl formamides.

- Alkyl isocyanides have the general structure R-N=C=O.
- When treated with acidified water, the isocyanide undergoes hydrolysis.
- The reaction can be represented as follows:

\[ R-N=C=O + H_2O \xrightarrow{H^+} R-NH-COOH \]

- The product formed is an alkyl formamide (R-NH-COOH), confirming that the assertion is correct.

### Step 2: Analyze the Reason
**Reason:** In isocyanides, carbon first acts as a nucleophile and then as an electrophile.

- In the structure of isocyanides, the carbon atom is bonded to a nitrogen atom and has a partial positive charge due to the electronegativity difference.
- Initially, the carbon can act as a nucleophile because it has a lone pair of electrons that can attack an electrophile (like H⁺ from acidified water).
- After the initial attack, the carbon can become positively charged and act as an electrophile in subsequent steps of the reaction.

### Step 3: Conclusion
- Both the assertion and the reason are correct.
- The reason provided explains the mechanism by which the assertion occurs.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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