Film Container CO2 Rocket.

Step 9: Fin.

That's all folks, you're ready to launch.

Take your little film rocket to an open area, making sure to keep it upright during transport. (I once carried one of these all the way from home, on the bus, and to fourth period).

To launch:

1) Set the film canister on the ground in your launch area.
2) Take a few deep breaths.
3) Turn the film container onto its top.
4) RUN AWAY!!!
5) Watch from a safe distance.

I thought of putting a video on here which I made of a launch, but I had a great deal of trouble converting my camera's weird-o format and whatnot. My most recent garage experiment shot the rocket up to 10 feet (3m) at which point it banged into the ceiling with a satisfying hollow pop.

PLEASE BE CAREFUL, you might poke out your eye, or at least make it a bit sore.

How does it all work?

I'm glad you asked. Most everyone has seen the simple baking soda + vinegar reaction which produces a nice foamy mess. That reaction is the engine of this rocket. The TP acts as a triggering mechanism by separating the components of the chemical reaction until such time as you turn the bottle over. At which point the chemical reaction starts to produce carbon dioxide. Once the pressure is sufficient so that the seal on the cap is unable to contain it, the thing goes shooting up in the air with a bit of noise and some splashing.