Seltzer Popper Launches Glow Stick

I discussed in previous blog entries how pressure from chemical production of carbon dioxide can be used as the basis for propulsion. The carbon dioxide can be produced by reaction between acids and carbonate salts. The picture below shows a rocket based on the popular demonstration involving water and AlkaSeltzer® in a 35 mm film canister placed on a chassis made from LEGO® parts. The "fuel" for the popping canister demonstration is approximately half an AlkaSeltzer® tablet, which is placed into a 35 mm film canister (Fuji-brand film canisters seem to work best). Water is added to the canister (to fill it approximately one third to one half full) and then the canister is capped. Ordinarily, in demonstrating these sorts of poppers the canister is placed upright, but in this case the canister is placed upside down and a bit of poster putty is used to hold a glow stick upright on the canister.  The force of the popper explosion is sufficient to launch the glow stick a few feet into the air. ABOVE: The glowing popper rocket assembly. BELOW: Launch of a blue glow stick popper rocket.  The orange glow stick popper rocket has not launched.