On this morning we spend the time setting up for make-up labs and making up molecular modeling sample sets for the AP kids to play with later. Apparently the bio kids put together some organic molecules, glycine or glucose or what have you. One of the plastic bags for a molecule was labeled sucrose, which is a big molecule to build out of a molecular modeling kit. In addition to Ms. Bio’s handwriting on the label of “Sucrose (a disaccharide)” a student had written, in pencil, “I pity you.”
We also set up a demo I was going to do later for the Chem 1 kids, showing how gas can be collected over water to justify the utility of Dalton’s Law of Partial Pressures. I also ran it once to make sure I had seen it working once before debuting before the student, and to get a sense of how much zinc and acid I would need to provide a visible amount of gas to collect.
We got into a conversation about Mr. CT’s chemical spill stories. Apparently while he worked in another school in the same area some student had broken into the Chem room and decided to play catch with a container of sulfuric acid. The police had an easy time following them from the trail of shed clothing they left. Unfortunately, the local fire departments are the ones who deal with chemical spills, so when they get to a chemical spill that is also a crime scene, they have to check up on the police officers that might have been walking through the spill to investigate the crime. After checking to make sure they’re feeling alright, a good thing to check is the bottoms of shoes for damage. Mr. CT also told the story of how he had to get the administration to call an evacuation of a school due to an unknown noxious gas. It turned out to be a prank involving pepper spray in a garbage can that happened to be in the hallway by the chemistry rooms.
We also finally got in the registry codes for the last thing that the student need to register for in Chem 2. So I got one and registered as a student as a dry run, to make sure everything worked.
AP – They did a molecular modeling lab today, working with the physical modeling kits to help get the geometry of different bonding structures in their heads. One group asked what the electronegativity of xenon was, since it didn’t appear in the books they were using and they needed to know how polar the Xe-F bonds were. Since I don’t know something like that off the top of my head, I pulled out my iPhone with the free version of The Chemical Touch and looked it up for them. This prompted a comment of, “Oh, I like him!”
Chem 1 – Today we reversed the roles we had yesterday, Mr. CT answered questions on the homework and I went through the lecture section, covering the combined gas law and Dalton’s Law of Partial Pressure. The fourth period didn’t have a whole lot of pre-lecture homework to go over due to working through Channel One time. Mr. CT went over the homework, highlighting some weirdness from the significant figures that got through. Then it was my turn!
I had mucked around a bit to make the Power Point work better for me, but it was still someone else’s lesson plan in someone else’s teaching style. I feel like when I’m on my own in the big, lonely world that the methods I will use will diverge sharply from the way that Mr. CT has set up his class. However, Mr. CT’s methods seem to be working pretty well for him, so it will be nice to see what I can learn from a method that is outside my comfort level. Anyway, today’s lesson had some algebraic derivations that wasn’t confident in how well they worked on Power Point, since it is much harder to use the spatial sense of the variable manipulations. So I spent the time bouncing back and forth from the PowerPoint to the chalkboard, having to reach up and turn on or off the projector and bring up or down the screen. I also realized I should have worked out the problems beforehand so that I knew all the answers and could speed up confirmations. The whole thing was a little awkward in ways I can definitely improve with preparation: working out problems beforehand and writing up different things to leave on the board to make for less writing during the class.
The demonstration I gave of collecting gas over water went really well, and I think I got a fair bit of showmanship out of it. I also handed out a chart that they were supposed to keep in their notes which consisted of the vapor pressure of water at different temperatures. I hinted at things to come while doing this, drawing attention to the fact that, at 100 oC the vapor pressure of water just so happens to be 760 mm Hg, which just so happens to be atmospheric pressure! It seemed to fit and Mr. CT seemed to appreciate.
The class ended with a bunch of free time for them to work on homework, which was a little awkward. Mr. CT’s response to this was to work through the homework problems for longer in the next class. I found that a little odd, but whatever. I got the presentation aspects better in the subsequent classes.
Chem 2 – I provided my computer to display some stuff to show the class, nothing I noted beyond that.