Given below are two staements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : Butan-1-ol has higher boiling point than ethoxyethane .
Reason R : Extensive hydrogen bonding leads to stronger association of molecules.
In the light of the above statements , choose the correct answer from the options given below:

Options

A. Both `A` and `R` are true and `R` is the correct explanation of `A`
B. `A` is true but `R` is false
C. Both `A` and `R` are true but `R` is not the correct explanation of `A`
D. `A` is false but `R` is true

Answer

To solve the problem, we need to analyze the given Assertion (A) and Reason (R) statements regarding the boiling points of butan-1-ol and ethoxyethane.

### Step 1: Understand the Structures
- **Butan-1-ol**: This is a straight-chain alcohol with four carbon atoms (C4H10O). Its structure can be represented as:
\[ \text{CH}_3\text{CH}_2\text{CH}_2\text{CH}_2\text{OH} \]
- **Ethoxyethane**: Also known as ethyl ether, it has the structure:
\[ \text{CH}_3\text{CH}_2\text{O}\text{CH}_2\text{CH}_3 \]

### Step 2: Analyze the Boiling Points
- **Boiling Point of Butan-1-ol**: The presence of the hydroxyl group (-OH) in butan-1-ol allows it to form hydrogen bonds with other butan-1-ol molecules. This leads to stronger intermolecular forces, resulting in a higher boiling point.
- **Boiling Point of Ethoxyethane**: Ethoxyethane, on the other hand, does not have an -OH group and cannot form hydrogen bonds. The intermolecular forces present are primarily Van der Waals forces, which are weaker compared to hydrogen bonds.

### Step 3: Conclusion on Assertion
- Since butan-1-ol can form hydrogen bonds while ethoxyethane cannot, butan-1-ol will indeed have a higher boiling point than ethoxyethane. Thus, the assertion (A) is **true**.

### Step 4: Conclusion on Reason
- The reason (R) states that "extensive hydrogen bonding leads to stronger association of molecules." This is also **true**, as the hydrogen bonds formed between butan-1-ol molecules are responsible for the increased boiling point.

### Step 5: Relationship Between Assertion and Reason
- The reason provided explains why the assertion is true. Therefore, both the assertion and the reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
- The correct choice is: **Option 1: Both assertion and reason are true and reason is the correct explanation of assertion.**

---