Homework 5/6 #8

[705903057]

Calculate the standard molar entropy of vaporization of water at 45.0 °C, given that its standard molar entropy of vaporization at 100.0 °C is 109.0 J-K-'-mol-' and the molar heat capacities at constant pressure for liquid water and water vapor are 75.3 J.K-'-mol-' and 33.6 J-K-'-mol-', respectively, in this temperature range.

This was one of the problems I never ended up figuring out how to solve. Any help would be appreciated! Does anyone know how to solve?

[205873468]

Using the entropy change of vaporization equation, we can plug in the values we are given. (75.3×ln(373.15/318.15))−(33.6×ln (373.15/318.15)=
ΔS vap∘=(75.3×(−0.1623))−(33.6×(−0.1623)) = −6.977J/(K/mol)