Recently I wrote a post for the Jacksonville Moms Blog highlighting some of my favorite science experiments for big kids. These were all done for the Mad Science Party we threw for Cole's 8th birthday. Here are the details for the Exploding Film Canister Experiment.
Exploding Film Canister
Directions: Fill the film canister 3/4 full of water. Add Alka-Seltzer (generic brand works just as well) tablet and close the lid tight. Stand back and watch the lid shoot off into the sky.
Why it works: When the tablet hits water, a chemical reaction takes place very quickly. The bubbles are carbon dioxide gas (CO2) and there’s a lot of it! In the closed canister, the CO2 builds up so much pressure that the lid is forcibly removed from the inside.