How to start thermodynamics

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Hi all,
this is sort of a clicker question but more general. Our first year goes like this:
week 1 general intro, matter
week 2 molecules and ions
week 3 stoichiometry, mole concept
week 4 basic reactions in solution (ppts, redox and acids and bases, but all revisited later)
week 5 gases
i.e. so far EASY.
Then week 6 midsemester exam. Then week 7 - BOOM thermodynamics. Today I was going through my old slides (inherited and modified) and trying to work out what clicker questions to ask when, but in fact I think I need to re-do the whole lot. It is SOOO hard. The first 44 (I kid you not) slides are definitions eg system vs surroundings, +ve vs -ve heat, Hesses law, etc etc. It is boring, dry, puts the students to sleep and hard to follow. Does anyone have a better approach that you can share?
Thanks,
Madeleine

cfellows's picture

I think I sent you my lecture slides already. :)  They struggle with it here as well being so early in the semester. I think sticking thermometers in beakers of exothermic and endothermic reactions in front of them is a good way to start. Ruthlessly pare away all definitions they won't really need in chemistry. And memorise Eddington's quotation about the 2nd Law and recite it in an awed voice!

Madeleine Schultz's picture

I did try to get rid of some of the definitions but I feel like they do end up needing most of them. Somehow entropy is easier and makes more sense than enthalpy. Dan S sent me an inclass activity that I will be doing this Friday. I will also show this movie:
http://chemed.chem.purdue.edu/demos/main_pages/21.1.html
The class is such a big mix of people who have never done chemistry, some chem and some from good schools who have done a lot so it is hard to be at the right level for everyone. I think the clicker questions I am asking are really helping with engagement (we shall see whether they agree!).

A good type of clicker question is the 'Thermodynamics of the Piston':-
Consider a frictionless piston with insulated walls (the adiabatic case). A block of wood rests on the piston. Does property X increase, decreas or stay the same when the block is removed. The problem can range through the thermodynamic variables (P,V,q,w,H,S,U). The most interesting one is S (increase since volume increases or decreases due to temperature decrease?) - the second law gives the answer (no change in surroundings so S must increase by second law)