empty film canisters (clear containers with insert lids work best)
water
Alka Seltzer
googles (if available)
toliet paper
Concept: When the Alka Seltzer dissolves in the water it starts to form a gas (carbon dioxide). The gas bubbles keep building up and the pressure from the gas explodes the canister.
Procedure: Fill the film canister 1/2 way with water. Place a piece of toliet paper over canister and push in just enough to keep from getting wet, while forming a nest for the Alka Seltzer. Place the Alka Seltzer in the nest. Place the lid on canister and carefully tear away excess toliet paper. Turn film canister upside down and watch for explosion. Be careful to not lean over canister due to quick reaction time.
Extension: Use other ingredients to make the film canisters explode (lemon juice and baking soda, vinegar and baking soda). Try filling three different canister with three different ingredients. Measure which lid or rocket flies the highest.
Application to Real World: Carbon dioxide is a natural chemical substance (primarily in gas form). It is not toxic, unless in very high quantities. Carbon dioxide is a vital substance to life on Earth. Plant life needs carbon dioxide to function and give off oxygen. Without carbon dioxide, there'd be no plant life! However, carbon dioxide in the Earth's atmoshere is known as a "greenhouse gas." Greenhouse gases absorb heat radiated down by the sun and send the heat back down to the planet to maintain temperatures. The issue is that more carbon dioxide acting as a greenhouse gas in the atmoshere means more heat is trapped and sent back down to a planet unable to absorb or convert it all. This is what global warming is all about.
