Studying phase changes is not quite as interesting as it might sound :) Actually, depending on the demonstrations I am doing that day, it isn't so bad. On this particular day, the thrill was simply talking about how a toilet works, which, on the hole, isn't actually a phase change, though it does involve at least a couple of phases, and sometimes all three.
The principle we were looking at was how a siphon works. It is actually pretty amazing to watch when a siphon takes over. I have a tantalus cup in class that shows the basics behind the siphon tube in a toilet's bowl. When the siphon is completely full of water, it drains itself and the bowl. Pretty slick.
SJ.
