Most rockets create thrust - the force that propels them forward
- by an exothermic chemical reaction that generates gas. You can
find out more about rockets HERE.
In this project you can make a rocket fueled by a chemical
reaction that produces carbon dioxide. Make sure you launch this
rocket outside and wear safety goggles - it's very messy and can
fly a long way!
What you need:
- One emptry 35mm plastic film canister and lid. The white
(almost transparent) film canisters work better than the black
canisters with the grey lids. You should be able to get these from
any shop that develops film.
- One Alka-Seltzer or other antacid table (ask your parents to
get this for you).
- Water
- Safety goggles
What to do:
Put on the safety googles and go outside.
Remove the lid from the film canister and put a teaspoon (5ml)
of water in the canister.
Break the Alka-Seltzer in half.
Do the next two steps very quickly
Drop the Alka-Seltzer into the canister and put the lid tightly
on the canister.
Put the canister on the ground with the lid down and step back
at least 2 metres.
About 10 seconds later you will hear a large pop and your
canister will launch into the air.
Caution: if it does not launch, wait at least
thirty seconds before examining the canister. Uusally the cap is
not on tight enough and the carbon dioxide has leaked out instead
of building up.
How does it work?
The water dissolves the Alka-Seltzer tablet and starts a
chemical reaction, which produces carbon dioxide. The carbon
dioxide starts to build up, which increases the pressure inside the
film canister, until eventually the cap is forced off and the
rocket blasts up. This system of thrust is exactly how real rockets
work, only they use rocket fuel instead of Alka-Seltzer.
These two videos will show you a film canister rocket in action.
In the second one the film canister rocket has been customised with
fins and a nose cone to help control the rocket's flight.
Or watch on YouTube.
Or watch on YouTube.