For years my students would heat the hydrates in glassware, burn themselves, break the glassware and splatter salts and thus their data, all over the lab bench. A few years ago Bob Worley came up with a great microscale technique. Essentially, it takes a used bottle cap without the plastic and this is used as the dish. Next, there is about a three inch machine screw that goes through a drilled hole in the cap. A nut is placed on the screw to hold everything in place and cheap pliers are used to hold the entire assembly over the flame.
I have always been intrigued by the story of the Hindenburg, the iconic airship that caught fire on May 6, 1937. The accident killed 35 of the 100 passengers and crewmembers on board. As a chemistry teacher, I discuss this from a chemical standpoint and the fact that the airship was filled with hydrogen, a flammable gas, rather than helium, a non-flammable gas, as today’s modern airships are.
I have to be honest. I am not big on showing videos that take up a whole class period. Most videos I try to make or get off of You Tube and usually I can asign them for homework. I never want them to be more than ten minutes long.
I have a confession: thermodynamics is not my strong suit. The data set I got from the College Board confirmed my lack of confidence in the summer of 2015. With the hope of improvements, I spent some time revamping my thermo unit and I implemented it near the end of last school year. I will share an activity that I feel was quite formative for students and for me in making connections among thermodynamic principles and equilibrium.
The first few experiments and labs that I use to start the year off are more like “probes”. I am trying to figure out the strong and weak points for my students. I have found a couple of things we can work on. The two major areas are observations and communication. We need to work on writing sentences that use data and background information to support the theories students develop.
Red dye #40 found in strawberry Kool-Aid and various cloth fibers can be used in a very simple experiment that can teach students about intermolecular forces. A video is included that describes the experiment and analysis of results.