A year ago, I decided to modify my Discussion Board participation in my G-Chem classes to feature weekly prompts that the students respond to. You can read what prompted me to do so in this post from a year ago. It’s a way for me to engage students outside of class, is not onerous for the students (the minimum response to weekly prompts is 120 words), and hopefully it gets the students thinking a little more broadly about the foundations of what they’re learning.
Here are my G-Chem 1 prompts from last semester along with minor commentary from me. They are still somewhat haphazard, but I expect to improve coherence now that I’ve done a year’s worth covering both semesters. Week 1 was us introducing ourselves. I had a short list of “who am I” questions, and started the ball rolling by answering those questions myself. We also skipped the week of Thanksgiving since that was only a half-week, and students needed a break.
Week 2: Analysis
The process of breaking something down into its smaller parts is called Analysis. We've discussed atoms as being the fundamental parts that make up molecules and matter. Can matter be fully described by "the sum of its parts"? That is by breaking something down into its fundamental parts, can you understand what it is (or how it works), or might you lose some understanding in the process? Provide an example as you think about these questions. (If it's helpful: The reverse of Analysis is Synthesis. Another way of thinking about these questions is whether Analysis and Synthesis are the exact opposite of each other.) Like many of the questions you'll see in subsequent weeks, there is no easy right or wrong answer to these questions - that's why this is a discussion!
I was a tad ambitious in my Week 2 prompt, but it did set the stage for what we were going to be doing for much of the semester, and how to think about scientific activity in more general terms. I was likely influenced by my summer reading about the limits of reductionism, even though it remains extremely useful as a process in science. Students were a little stumped, but there were some interesting and thoughtful responses.
Week 3: Elements
On the first day of class, we talked about the simplicity and versatility of Aristotle's Four Elements (Earth, Water, Air, Fire), but modern chemistry has chosen a different (possibly messier and less versatile) way to classify elements. Today, scientists have "identified" close to 120 elements. And although isotopes exist, we have chosen not to label them as different elements. What do you think about the way elements are classified? Could different choices have been made? Feel free to speculate on creative possibilities.
This got students thinking a little more strategically about the periodic table and how one might represent information. Most students said they liked the periodic table and thought it was both compact and useful although they had trouble articulating why specifically. Most had simply never thought about it and found it interesting to ponder why isotopes aren’t specifically included and there were some suggestions of how to do so.
Week 4: Otherworldly Vision
If life was found on other worlds, would organisms have evolved eyes? (Why or why not?) If an organism did evolve an apparatus for vision, what might their world look like to them and how might that view be different from alien human Earthling visitors to their world (if interstellar tourism was safe and possible)?
I had just talked about the electromagnetic spectrum in class and I ended with discussing the solar spectrum of our sun, what we consider visible light and how different organisms (for example those that lived in caves) may have receptors for slightly different wavelengths. My last slide was a speculative image with an artist’s impression of different colored flora on a different planet. I threw in some speculation about red-dwarf suns and habitable planets. Students found this prompt interesting.
Week 5: Fuzzy Knowledge
Chemistry is all about the behavior of electrons in atoms. While we know the mass and charge of an electron, it turns out there are many other things we don't know, for example its size, or where it is located in an atom (Bohr was wrong about the orbits). It's not just that we don't know, but we fundamentally CANNOT know (Heisenberg's Uncertainty Principle). We can only describe electrons in probabilistic terms. What do you think about this "fuzziness" in our knowledge of electron behavior? Is it strange that we know the mass and charge but can't know other things?
Students didn’t like the idea of Heisenberg Uncertainty’s Principle. I wouldn’t have known this from our class discussions without asking students their opinion in this prompt. Most thought that we simply haven’t invented the appropriate technology yet – this is a rational and reasonable response given the strangeness of the idea of what we know and do not know about fundamentals. So, while there wasn’t much probing discussion, I learned something from reading their responses.
Week 6: Quantum Rules
Last week we discussed quantum numbers, their rules, and their restrictions and how those might have led to the arrangement of the periodic table (that's not what happened historically but it's interesting to think about). If one of the quantum number rules were different, how might that change the arrangement of the periodic table? Would there be shorter or longer rows? Might the shape change? Suggest a speculation!
This was less interesting engagement than I anticipated. There were some good ideas, but most were very routine with a minor perturbation. Little depth for the most part. But a small minority of intrepid students did engage in a way I was hoping.
Week 7: Elements Again
Choose an element in the Periodic Table. It cannot be one that someone has already posted (i.e. skim through the list before you write). You should say something about how the element got its name, how it was "discovered" (or synthesized), and at least one other fact about it that you found interesting and WHY you found it interesting.
I worded this prompt, not just to get students to do a little web-surfing (Wikipedia mostly), but also to read or at least skim the responses of others. This did happen in previous weeks, but not always. The very last part – asking students to articulate why they found something interesting – allowed the students to share something about themselves, and that’s what I found most interesting to read. (I already knew a lot about the history of the elements, I highly recommend this book for the interested reader!)
Week 8: Two Surprises
We've made it through the first half of the semester, hurrah! Time for a short reflection: What are two things you found surprising from CHEM151 in the first half of the semester and why?
Of all the prompts, this was the one I enjoyed reading most because of the interesting and varied student responses. One recurring theme was students mentioning that in their previous (high-school level) chemistry courses, the electron wasn’t perceived by them as being so central to chemistry. I talk about electrons all the time in class, and the students picked up on it – in hindsight that’s not surprising. The Heisenberg Uncertainty Principle came up a few times, as did wave-particle duality. A number of students commented about the depth and pace of the class (i.e., deeper and faster-moving), and seeing some topics they learned in high-school illuminated in much more detail. Some were pleasantly surprised that chemistry was not as bad as other people had told them, even though it was still hard. (I’m upfront about it being a challenging subject.) All that being said, here’s my favorite student response:
“One thing I found surprising about CHEM151 in the first half of the semester is how many open, unanswered questions come from answering one question. Out of all the questions we pose and can solve in chemistry, there are hundreds of unanswered questions that develop from that one answered question. I cannot seem to wrap my mind around how much we do not know about our universe. One other thing I find surprising is how long it takes us to discover and solve new answers. Out of all the years on this planet, it has taken decades to solve questions and the main question about how does the universe work has not been solved. It takes forever to solve the questions asked on this planet, so how long will it take until we finally understand our planet, let alone our universe or other planets?”
Week 9: Covalent Life
While living organisms utilize metals, the vast majority of compounds are covalent, formed from non-metals and predominantly C, H, O, N (with smaller amounts of S and P). Carbon, in particular, forms the backbone of almost all these compounds. Life predominantly uses only a few elements in the periodic table. Any thoughts or speculations as to why this might be? Is there something special about covalent compounds, or about carbon? Is there something puzzling about this?
Probably a bit too ambitious, and not enough background provided by me. There was some discussion from the students about valency, but not much about localized bonds, relative bond strengths, etc. I probably hadn’t provided enough background to tackle this beyond the superficial. I used to talk a little more about this in class, but last semester I ran out of time during my bond energy class activity.
Week 10: Structure/Function
Generally speaking, in chemistry, the thinking is that Structure determines Function. You analyze the structure first, and use that as the basis to determine how the molecules/compounds will behave and what properties they will exhibit. In biology, it's the other way around: Function determines Structure. You start with the function and use that as a basis analyze the structure to learn how it evolved to support the function. To throw in a third category, for human-made ("engineered") objects usually referred to as Artifacts, we (humans) have a function in mind before designing a structure to support the function - although sometimes we can be quite creative and use an existing structure for a different and possibly novel function that was unanticipated. What do you think about this?
This is a broad question I’m still puzzling over but I decided to throw it out to the students to see what they thought. There’s a range of student interests in my class. Many of the students are taking biology but there is a small yet significant contingent of engineers. A number of students provided good examples and analogies for their arguments. Our in-class chemistry examples had all consisted of “structure determines function/properties” – part of my emphasizing that chemistry is about explaining macroscopic (and even some microscopic) observations from nanoscopic atomic or molecular level structural information.
Week 11: A Chemical Reaction
Write one balanced chemical reaction (that involves bonds being made and broken). For each substance in the chemical equation, state (1) whether it is covalent, ionic, or metallic, and (2) whether it is a solid, liquid, gas, or in aqueous solution, under the conditions of the reaction. Then in a couple of sentences, tell us why you think this reaction is interesting -- presumably why you chose it. The reaction you choose should not already have been chosen by a previous student.
I was likely in a rush when writing the above prompt and hadn’t given much thought to how to tie in stoichiometry and chemical reactions that we were doing that week. Not much to say here.
Week 12: Compounds
Today in class I mentioned that one of the easiest and most general ways to figure out the chemical formula of a compound, and thus the ratio of its elements within that compound, is to burn it. Respond to one or more of the following questions (you don't have to respond to all of them): What do you think about this? Why might my statement be true (or under what conditions)? Might there be any limitations to this method? Are there alternative methods you can think of that would help us do this (perhaps for a more specific or limited class of compounds)? Why might anyone care?
Hah! Students were surprised and intrigued by my proclaiming that burning was one of the most efficient ways of figuring out chemical composition. Some thought that it only worked for covalent compounds, allowing me to chime into the discussion of how it might work for ionic or metallic solids.
Week 13: Evaluation
Before answering this week's prompt, first go fill out your Student Survey of Educational Experience at the link below for this class. It should only take about 10+ minutes. Then, come back here and let me know how you feel about the format of our weekly Discussion Board prompts. This is something new I've been doing since last year and I've been tweaking the format each semester partly based on student feedback. If there's something you liked, or something you thought could be done better, write your comments below so I can take them into account when planning my course next semester. (For this week's prompt, there won't be a length minimum, so if you didn't have any strong feelings either way you can just write one sentence to that effect and I'll count it.)
In short, students responded positively to the prompts. Many didn’t feel strongly about them and were upfront about liking a low-key way to earn free points for not too much work. A few enjoyed the brain-tickling broad questions. Some mentioned that it added to a community feel to the class and hearing, or in this case, reading their classmates’ thoughts and opinions. That was enough to make me continue doing this, although I need to tighten up some of the prompts. I also had a decent response rate on my evaluations, having prompted the students to do them without using any class time for it.
Week 14: Chemistry Everywhere
Last discussion board prompt! Pick a career/job/gig that illustrates how chemistry might play a role. This may be something you're personally interested in or something you think would be cool even though you wouldn't make a career out of it. While there are many careers that clearly feature chemistry (medicine, pharmaceuticals, materials, batteries, environment, etc.), feel free to be creative and come up with a job that might not yet exist. Hopefully after you've all had your say, we will see chemistry everywhere! I'll start the ball rolling.
This last one was prompted by discussions in our department meeting about whether we are losing majors and whether students are just not aware of what they can do with a degree in chemistry or biochemistry. And since students will probably spend some time over the winter break thinking about their major (for those who were still undecided), I thought it would be interesting. I started the ball rolling with an imagined “4D Video Game Designer” to get the creative juices rolling. Some students picked things within their major of interest (many in science or engineering) but several branched out and picked things they wouldn’t likely do themselves, but thought would be interesting to imagine.
We’ll see how things go this coming semester! We’re starting remote for the first couple of weeks so the online engagement will be more important. I hope we are able to quickly and smoothly transition back to in-person. Students just seemed happy to be back in-person last semester. Me too!
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