Sodium bicarbonate rockets are often used in science classes to demonstrate principles of chemistry and physics.
After a short time, the pressure of the carbon dioxide is great enough to cause the body of the canister to be launched into the air with a popping sound.
The canister may be embellished with paper fins to resemble more closely a real rocket.
For example, students are sometimes asked to experiment with the amounts of water and Alka-Seltzer to find the combination which propels the rocket the greatest distance.
[1][2] Alternatively they may derive equations to calculate the speed and velocity of the rocket from the distance it travels.