entropy change for vaporization, ΔSvap , in J/(K ⋅ mol)?

Question

The boiling point of acetone is 56.1 ∘ C, and the enthalpy change for the conversion of liquid to vapor is ΔHvap = 28.51
kJ/mol. What is the entropy change for vaporization, ΔSvap , in J/(K ⋅ mol)?

Express your answer to four significant figures and include the appropriate units.






ΔSvap =

Value Units

Answer 1

I think you use ΔS = ΔH/T

 

Let's convert T first:   56.1 ∘ C + 273 = 329.1K

 

ΔS = [(28.51kJ/mole)/329.1K]  x  1000J/kJ  = 86.63 J/K mol