We combined our two laws to form an expression for the internal energy that was a function of the extensive variables S and V. This lead to formal definitions of thermodynamic variables T & P as wells as Maxwell relations. We also introduced H(S,P) which came from our definition of enthalpy. We had a brief discussion about the upcoming exam next Friday, with more details to come later. An old exam from 2008 has been posted online.

We also completed 2 of 3 practice problems. You should prepare the third one for class on Wednesday.

Reminder: we will not be meeting on Monday and Homework #4 is due Wednesday.

Summary - Slides - Practice Problems

We looked at how to determine entropy changes during different processes. We also examined how S for the system and surroundings are different for reversible and irreversible processes. Finally we figured out how to determine entropy changes as a function of temperature.

Summary - Slides

We examined entropy, spontaneity and applications to the Carnot cycle.

Homework #4 was distributed and is due next Monday.

Summary - Slides - Homework #4

We discussed some of the upcoming homework assignment and then completed the practice problems.

Have a great weekend.

We talked about how in incorporate phase transition into our understanding of thermochemistry. We then worked on some practice problems.

Summary - Slides - Practice problems

There have been several questions regarding part (c) of Question 1. You are asked to find Delta U, q, and w for the composite process, not necessarily each individual part. You cannot find q for each part since you are not given enough information to do the calculation. However, if you can determine U and w, you can then find q for the composite (entire) process.

We discussed the uses for enthalpy when working at constant pressure. We also explored the use of enthalpies of reactions and how to deal with non-standard states.

Summary - Slides

We explored ideal gases and the dependence of U and H on temperature. Two practice problems were completed to illustrate this relationship.

Homework #2 will be due on Wednesday, September 16

Summary - Slides

(Updated 9/14/09: Summary has been corrected)

Lecture summary and slides from today’s class. We discussed heat capacity as a way to relate heat transfer to a changed in temperature. Also looked at how to do calculations involving P-V work and an ideal gas.

Model solutions for Homework #1 are posted and Homework #2 was distributed.

Summary - Slides - Practice Problems

Lecture summary and slides from today’s class where we discussed different types of thermodynamics variables and the relationship between them. We also introduced different types of processes and systems that will be important in future discussions. Finally we came to the First Law of Thermodynamics and the concepts of work and heat.

Summary - Slides