Assertion : Molar enthalpy of vaporisation of | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The molar enthalpy of vaporisation of water is $40.7 \ kJ/mol$,while for ethanol it is $38.6 \ kJ/mol$.This difference arises because water molecu

Vedclass · Accepted Answer

If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.

Vedclass · Answer

(A) The molar enthalpy of vaporisation of water is $40.7 \ kJ/mol$,while for ethanol it is $38.6 \ kJ/mol$.This difference arises because water molecules exhibit stronger hydrogen bonding compared to ethanol molecules.Water is indeed more polar than ethanol due to the presence of two $O-H$ bonds and a higher dipole moment.However,the primary reason for the difference in enthalpy of vaporisation is the extent and strength of hydrogen bonding,which is directly related to the polarity of the molecules.Therefore,both statements are correct and the reason explains the assertion.

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

Similar Questions

Which of the following hydrogen bonds is the strongest?

In ice,the $H - O - H$ bond angle is closest to which of the following?

Which statement is correct?

The molecular interactions responsible for hydrogen bonding in $HF$ are:

The maximum possible number of hydrogen bonds in which an $H_2O$ molecule can participate is

Vedclass Test Series

Exam Paper Generator

Online Exam Module

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