Assertion : Molar enthalpy of vaporisation of | vedclass

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(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

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

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(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.

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