Question

The ΔHvap0 of a certain compound is 14.63 kJ·mol–1 and its ΔSvap0 is 82.48 J·mol–1·K–1. What is the normal boiling point of this compound?

Answer 1

let me tell you a shortcut!!!!

you see you want to calculate the temperature!!!! right!!!

so juts look at the units and take ratio of the given data to get unit K. as unit of temperature is K

so i m sure you might have guessed what ratio should be of

and that is (ΔHvap0 / ΔSvap0 ) = (14.63 X 10³ / 82.48) = 177.37 K

Now to come to the explaination

delta G = delta H + T delta S

The system is in equilibrium between the liquid and gaseous phases at the boiling point, so :delta: G_vap=0 and we can rewrite the equation as
T = delta H/ delta S