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DIY Canister Rocket


Blast off from your own backyard with team GCM member, Essence’s fun science experiment. Learn how to create rockets out of simple ingredients and a little chemistry.

Materials: Capped film canister Alka-Seltzer tablet Water Safety glasses Decorative rocket items (optional)

Directions:

  1. If you would like, you can start this project by decorating your rocket with household materials like paper, markers, ribbon, and beads. Decorate so that the bottom of the film canister (the side without the cap) is the top of your rocket and the cap side is the bottom. Be sure not add anything that is too heavy, or obstructs the canister from being able to sit straight up on the cap.
  2. Prep your launch area. Make sure the canister will launch from level ground. Clearly mark where the rocket will launch and where you will stand while you wait for the rocket to launch. This should be about 10 feet away from the rocket.
  3. Make sure everyone involved with the experiment is wearing safety glasses or stand at least 10 feet away
  4. Fill the canister until it is about ¼ full of water. 
  5. In one swift motion add ½ of an Alka-Seltzer tablet to the canister, close the canister with the cap, then flip the canister over so it is sitting on its cap. Immediately retreat to stand and watch about 10 feet away from the rocket.
  6. It should take about 10-15 seconds until you hear the “pop” sound and the rocket takes off.
  7. Feel free to repeat the experiment

Experiment not working for you? Here are some tips:

    • Note. If your rocket does not take off. Be careful approaching it again. It could take off without warning. 
    • The lid must be on completely. If water and gas is able to escape from the canister, it could prevent the necessary build up of gas pressure within the canister to cause it to blast off. Make sure you have a seal that is air tight. 
    • If your canister pops off the lid, but doesn’t go very high up, this could be because you added too much water, or your rocket is too heavy from decorations. The water was too heavy to allow the rocket to go any higher. Try adding less water or remove some decorations next time.

What’s the science behind this experiment?

Alka-Seltzer and water mixed together prompts a chemical reaction that releases carbon dioxide gas bubbles. As this reaction is trapped in the canister, the canister fills with more and more carbon dioxide gas as the tablet is consumed by the water. The buildup of carbon dioxide produces pressure on the inside of the canister until the pressure forces the canister free from the lid. The sudden release of pressure causes the iconic popping sound and the canister to shoot up into the air!

Team GCM Creators: Essence 

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