Boyle’s Law, Cartesian diver

Tonight is chem lab night for Susanna and two friends. Our ordinary lab manual is excellent, but the lab for Boyle’s Law seemed far too complicated to reinforce the concepts involved, and it lacked illustrations to make clear the relation of the procedure to the principles at work. So on the fly, we changed gears, and decided to demonstrate the volume-pressure relationship of Boyle’s law with a Cartesian diver. The girls, along with Jackson, their comrade cousin in Missouri who joins us by video chat, began by searching youTube for “Boyle’s Law” and for “Boyle’s Law, Cartesian diver,” and then adapted the procedure to use a 2-liter bottle, a glass eye dropper and some food coloring. The diver made for a cool, kinesthetic demo of Boyle’s pressure-volume relationship for gases, and made an ideal segue for applying Boyle’s Law to “the bends.” Instead of a confusing lab that would have brought frustration while obscuring the principle, the result was a lot of thinking, learning and fun! See for yourself…