First Week of Class Report

I survived the first week of my new revamped course, and I have to say I really enjoyed putting together the material and watch my students mull over some interesting questions about energy and nuclear chemistry. The majority of my students read Feynman’s article before coming to the first class, and in the following two classes we looked at the source of nuclear energy (coming from the mass defect), and fission and fusion reactions. In one of the group exercises, I had eight groups calculate the binding energy per nucleon with a different isotope in each group and we were able to generate the binding energy curve in 15 minutes. I did underestimate my class preambles before group work resulting in less time for full class discussion (10 minutes at best), however we managed to talk about the solar irradiation curve and think about the “type” of energy we get from the sun, and how much reaches the surface of the earth. This is our transition into thermochemistry coming up this week, and I have a series of activities planned around fuels. We will look at fossil fuels, natural gas, calculate fuel efficiencies, discuss practical considerations, and maybe even come up with “designer” fuels.

I’m using a flipped classroom approach, in the sense that students do reading and have online homework to make sure they understand the basics before coming to class. In class is where we solve interesting and more challenging problems and discuss the trickier concepts. Overall my students have so far been good about coming prepared but as the semester wears on and they get busy, this may be progressively more challenging as their other classes pick up the pace. I typically start my class at a blistering pace and then ease off towards the end so that the weight of my class load contrasts with most of their other classes. While this is good in the long run for the students, they might have gotten a little shell-shocked from class this week. (So far no one has complained about the workload.) I’ve tried to design the out-of-class work to take no more than 6-7 hours per week. Since this is a 3-credit hour class, the students will spend an average of 9-10 hours for this class, which is about right, and they should be able to balance the workload.

The problem is how much time I am spending on the class. This past week I spent close to 25 hours on this single class. That’s closer to rookie class prep time, or what happens when you teach a brand new course (which I suppose is almost what I’m doing). For the typical 3-credit hour general chemistry courses I’ve taught, I also spend 9-10 hours per week on average, similar to the students. This includes class time, class prep, grading, and Q&A in office hours and over e-mail. I have to try and get this down to 15 hours a week if I’m going to survive. I got no research of my own done although I did help my research students move their projects forward, and I barely kept up with my administrative work as department chair. This coming week I need to work faster or be less ambitious.

The other thing I’m still working on is how to handle online class discussions. I would like what the students are learning in class to spark interesting thoughts on things that might seem unrelated to the class. I sent my students a proposed online participation plan to read over the weekend. I suggested one blog post with a minimum of 250 words per week, and three other entries (of any length) that could be blog posts, replies, discussion board threads, etc. In preparation for some of my classes I post videos with a few food-for-thought questions so that students have some fodder for online posting if they don’t have other ideas. I’m working on a rubric of how to grade the online work and my initial idea is to have students submit a portfolio three times over the course of the semester highlighting their best online contributions. Anyway, I’ll talk this over with my students in class this coming week and figure out how to proceed. Since I want them to take charge of their learning, it makes sense to give them some say over the syllabus and grading.

One thing I do like to do is give students examples so they know what to expect. Hence I wrote up a 308-word blog post shown below. I might cross-post some of them on this blog and vice versa so that I won’t have to do double work to keep up.

Nuclear Chemistry and an ARC Reactor

Going through nuclear chemistry this week, and thinking about different sources of nuclear energy, motivated to delve into figuring out how Iron Man’s Arc Reactor might work. Could it be possible to design a related compact energy source that is safe and reliable?

An article from the Huffington Post (http://www.huffingtonpost.com/quora/what-is-the-theoryconcept_b_3456241.html) outlines what we know about the miniature Arc reactor and speculates on the science and science fiction in building such a device. What caught my interest is the use of palladium in the reactor core, mentioned in the movies. In particular the author suggests the coupling of Pd-107 and Pd-103, whereby Pd-107 undergoes beta-decay, ejecting an electron that is eventually captured by Pd-103, and thus an electric cell is created.

Now if you wanted the energy of the sun in the palm of your hand, could palladium help you do that? Many moons ago, I studied reactions on metal surfaces, in particular trying to understand platinum catalysts. Palladium, which should be closely related to platinum and have “similar chemistry”, does something different with hydrogen. Palladium seemed to have the capacity to store subsurface hydrogen. One might speculate that compacting the hydrogen in palladium may provide conditions for the hydrogen to undergo fusion reactions and create vast amounts of energy. Sadly this is unlikely to work given there is no good mechanism to overcome the barriers needed for fusion, and the large amounts of energy involved would probably destroy the crystal structure of palladium possibly rendering the whole system useless.

Palladium was involved in the infamous case of “cold fusion” when Pons and Fleischmann prematurely reported that they had made a breakthrough device that allowed fusion nuclear reactions to take place at room temperature.  Maybe the Arc Reactor is just a pipe dream, but if it could be constructed, someone will be earning a lot of fame and money.