Question

Assertion : Molar entropy of vaporisation of water is different from ethanol.
Reason : Water is more polar than ethanol.

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

Answer 1

Answer: (B)

Molar heat of vaporisation of water is more than ethanol because of presence of stronger $H$-bonding in water as compared to ethanol due to which large amount of energy is required to break $H$-bond in $H _{2} O$. Ethanol is a volatile liquid due to weak $H$-bond.