Good afternoon scientists! My little scientist and I just watched our rocket blast off! It took a few tries with a little trial and error but it was worth the wait! 🙂
Film Canister (We bought a bag of them online)
Colored Paper OR Plain Paper with Crayons
**Do not eat or drink in a lab setting, wash hands with soap when done**
- Decorate the film canister as you choose. Add a cone for your rocket on the bottom of the film canister.
- Take your “rocket” outside in a safe, clear space with lots of room around. (When the rocket launches it will fly up, and land quite far, it is a bit unpredictable). Fill the film canister about 3/4 of the way up with water. Add half of an alka-seltzer tablet and cap tightly. Set the rocket down on the ground, cap side down.
- Move back away from the “rocket” and get ready for blast off. It takes a few seconds before it POPS.
Notes from experience: Our film canister was not getting a tight seal, there was a lot of water leaking out of the bottom. We had to add a layer of electrical tape around the rim. The rocket decorations got soaked before we were able to have our first successful blast off.
When we added the alka-seltzer tablet to the water a chemical reaction occurred. A chemical reaction occurs when two or more substances mix together and change into a new substance. When we added the tablets to the water the reaction caused a gas to form. As the gas built up in the film canister the pressure (force pressing on it) got stronger and stronger until the film canister could no longer hold together. When the canister popped open the rocket was able to blast off due to the building pressure releasing. The law of conservation of energy states that energy can not be created nor destroyed. We witnessed several changes of energy. When the film canister was waiting it blast off it was a form of potential energy. Potential energy is stored energy. We hear a loud pop when the film canister opened. The pop was the potential energy changing into noise energy. The launching of the rocket was a change of form of energy called kinetic energy or the energy of motion. Eventually the rocket is pulled back down to Earth due to gravity (the force that pulls an object to the largest object around it).