This week, we focused on Thermodynamics. We learned that entropy is the number of the most probable discernible microstates (or degrees of freedom) in a system which tended to be the most probable. Boltzmann's equation of entropy is S=klnW
Laws of Thermodynamics
1. energy contained in the universe is constant
2. the entropy of the universe is increasing
Basically, if delta S is positive, the particles in the system are moving faster (more randomness), or there are more particles in the product than the reactants. If delta S is negative, the particles are slowing down, or there are less particles in the product than the reactants.
In class, we worked on several worksheets, Thermodynamics II and Thermodynamics III, in order to understand the concept. We were also given some equations and changes in heat (or heat of formation) in order to find the enthalpy change of the system.
upcoming lab
There is a lab due next week on Friday. We are given a couple of reactions, in addition to the materials we need to find the heat of combustion for the reaction. We determined the equations for this in class. There will be more on this on next week's blog.
Main Ideas
This unit is probably the hardest unit for me. I understand the material whenever we go over it in class, but it takes me a while to understand the concepts of this unit, such as change in heat, enthalpy, and entropy. I still feel that I don't quite understand the general concepts of the topics I've mentioned, but I think it'll become more familiar when I review for next week's test. I was also confused on how the lab is going to work. How do we find the heat of combustion by doing the experiment? How do we get the measurements, let alone the accuracy of the combustion? For one of the steps, how do we create water from hydrogen and oxygen atoms? In summary, I don't feel confident about this unit, although it is starting to make a little bit more sense.
