Today was a good day at school.
I'd ordered some science supplies for all my classes and they arrived today. Well, not really today, but we've been on break, so I got them today.
The majority of them was Chemistry supplies, but there was some Bio stuff in there too (an electrophoresis kit and some frogs to dissect). Getting boxes full of SCIENCE is just fun. Especially since I've centered the vast majority of my demonstrations around the best type: Explosions.
My Chem class really isn't up to the proper section for reactions yet. We're still slogging out way through bonding, and I keep telling them we need to learn what bonds are before we start making and breaking them. We're getting there, but not quite yet.
However, I just couldn't help myself from doing a demonstration. One of the bits I'd gotten was calcium carbide which, when mixed with water, forms acetylene gas. The way I've seen this demonstration done previously was in a bottle into which a few small chunks were placed. They fizz and give off some gas, and then are ignited with a spark generator making a fantastic boom. All of my students jumped. This is all I did.
When I actually do the demonstration in the proper section, there's a further component to it: Instead of just dumping in a small amount, a heaping spoonful is tossed in. When the spark igniter is hit, absolutely nothing happens. The reason is that the acetylene gas pushes out all the air and without a proper stoichiometric balance, ignition can't take place. The students, meanwhile, are ducking under their desks.
I can't wait to get up to the proper sections to play with the rest of it.
Oh yeah, and I finally got a balance for my penny lab.