[Ann1234]

Hello! I have this problem that is driving me crazy-I am searching online but I can't figure out the answer. You are given the standard molar S of these 3 hydrocarbures and you have to predict the S for butane.

I know the answer is 310.1 from an online chart that I found here
http://www2.ucdsb.on.ca/tiss/stretton/database/organic_thermo.htm

But I don't understand how to get to that number.

Please help!thanks

What might you expect for the S of butane?

methane S^0 = 186.3 J/MOL K

ETHANE S^0 = 229.6 J/MOL K

PROPANE S^0 = 270.3 J/MOL K

[fledarmus]

What happens if you graph these three numbers against molecular weight? Number of carbons?