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AP EAMCET20227 Jul 2022Evening ShiftChemistryThermodynamics (C)Actual

The standard molar enthalpy of vaporisation ( _ vap H^ ) of A, B and C liquids is 23.3,41 and 29 ~kJ ~mol ⁻¹ respectively. The correct order of diople-dipole attractive forces in these liquids is

Options

  1. AB>C>A
  2. BB>A>C
  3. CA>C>B
  4. DA>B>C

Correct answer

A. B>C>A

Step-by-step solution

( The enthalpy of vaporisation is the amount of heat that must be added to a liquid substance to transform it into a gas. Dipole-Dipole interactions are intermolecular force of attraction between polar molecules. Stronger the dipole-dipole interactions, higher will be the heat energy required to break these interactions and vapourise the liquid. Since, the liquids A, B and C have molar enthalpy of vaporisation as 23.3,41 and 29 ~kJ ~mol ⁻¹ , the order of dipole-dipole attractive interactions will be B>C>A .

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