In the reaction,
`R-X overset(Alcoholic KCN) rarr A overset (Dil.HCl)rarr B`
The product B is

Options

A. alkyl chloride
B. aldehyde
C. carboxylic acid
D. ketone

Answer

To solve the given reaction sequence, let's break it down step by step:

### Step 1: Identify the starting material
We start with an alkyl halide represented as R-X, where R is an alkyl group and X is a halogen (like Cl, Br, or I).

### Step 2: Reaction with Alcoholic KCN
When the alkyl halide (R-X) reacts with alcoholic KCN (potassium cyanide), a nucleophilic substitution reaction occurs. The cyanide ion (CN⁻) acts as a nucleophile and replaces the halogen (X) in the alkyl halide.

**Product A**: The product formed from this reaction is alkyl cyanide (or nitrile), represented as R-CN.

### Step 3: Hydrolysis of Alkyl Cyanide
Next, we take the product A (R-CN) and treat it with dilute HCl. This step involves acidic hydrolysis of the alkyl cyanide.

In acidic conditions, the cyanide group (CN) undergoes hydrolysis, where it reacts with water (H₂O) in the presence of H⁺ ions from the dilute HCl. The CN group is converted into a carboxylic acid (COOH).

**Product B**: The final product after hydrolysis is a carboxylic acid, represented as R-COOH.

### Conclusion
Thus, the product B formed from the reaction sequence is a carboxylic acid.

### Final Answer
The product B is R-COOH (a carboxylic acid).

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