Propyl lithium reacts with ethene to give a compound `(A)`, which on reaction with methanal followed by acidic hydrolysis gives compound `(B)`. The compound `(B)` is :

Options

A. `Heptan-1-ol`
B. `Heptan-2-ol`
C. `Hexan-1-ol`
D. `Hexan-2-ol`

Explanation

To solve the problem step by step, we will analyze the reactions involving propyl lithium, ethene, and methanal, leading to the final product (B).

### Step 1: Reaction of Propyl Lithium with Ethene
Propyl lithium (C3H7Li) is a strong nucleophile. When it reacts with ethene (C2H4), it adds to the double bond of ethene. The reaction can be represented as follows:

1. Propyl lithium reacts with ethene:
\[ \text{C}_3\text{H}_7\text{Li} + \text{C}_2\text{H}_4 \rightarrow \text{C}_5\text{H}_{10}\text{Li} \]

This reaction results in the formation of a 5-membered ring compound (a cyclic structure) known as a propyl-ethyl compound.

### Step 2: Formation of Compound (A)
The product of the reaction between propyl lithium and ethene can be represented as:
\[ \text{Compound (A)}: \text{C}_5\text{H}_{10}\text{Li} \]

### Step 3: Reaction of Compound (A) with Methanal
Next, compound (A) reacts with methanal (formaldehyde, CH2O). The nucleophilic carbon in compound (A) attacks the carbonyl carbon of methanal, leading to the formation of an alcohol after the reaction:

\[ \text{C}_5\text{H}_{10}\text{Li} + \text{CH}_2\text{O} \rightarrow \text{C}_6\text{H}_{12}\text{O} + \text{LiOH} \]

### Step 4: Acidic Hydrolysis
After the reaction with methanal, the resultant compound undergoes acidic hydrolysis. This step converts the lithium alkoxide into the corresponding alcohol:

\[ \text{C}_6\text{H}_{12}\text{O} \xrightarrow{\text{H}^+} \text{C}_6\text{H}_{14}\text{O} \]

### Step 5: Identification of Compound (B)
The product (B) formed after the reaction with methanal and subsequent hydrolysis is hexanol. The structure of hexanol can be represented as:

\[ \text{Compound (B)}: \text{C}_6\text{H}_{14}\text{O} \quad (\text{Hexanol}) \]

### Final Answer
The compound (B) is hexanol.

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