Q. The enthalpy of vaporisation of a substance is 840 J/mol and its boiling point is $- 173℃$. Its entropy of vaporisation is
A) 4.8 J/mol/K
B) 12 J/mol/K
C) 210 J/mol/K
D) 49 J/mol/K
Explanation
(a)
$\mathrm{\Delta}S_{vap} = \frac{\mathrm{\Delta}H_{vap}}{T_{b}} = \frac{840}{173} = 4.8$ J/mol/K
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.