Question

Assertion (A): Ethers have lower boiling points than the boiling points of alcohols.
Reason (R): This is due to the presence of hydrogen bonding in alcohols.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false, but Reason (R) is true.

Hint:

Alcohols form hydrogen bonds (O−H); ethers cannot, so alcohols boil higher.

Answer 1

The Correct Option is A

Step 1: How to attack an assertion reason question.
First judge whether the assertion is true on its own, then judge the reason on its own, and finally ask whether the reason is the actual cause behind the assertion. The whole thing here turns on hydrogen bonding.

Step 2: Test the assertion.
Alcohols carry an O to H group, which lets neighbouring alcohol molecules grip each other through hydrogen bonds. Ethers, built as C to O to C, have no O to H and so cannot form these bonds. Hydrogen bonds hold molecules tightly, so more heat is needed to boil alcohols. That means ethers really do boil lower, so the assertion is true.

Step 3: Test the reason.
The reason credits the difference to hydrogen bonding in alcohols, which is precisely the cause we used. So the reason is true as well.

Step 4: Do they connect.
The hydrogen bonding in alcohols is the very reason ethers boil lower, so the reason correctly explains the assertion.
\[ \boxed{\text{Option (A): both true, R explains A}} \]