How to Make a Mentos Trigger Device If you thought the original Mentos & Diet Coke Experiment was a mess... email to friend
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1. Carefully open the bottle of Diet Coke, so it doesn't fizz too much.
2. Have an adult drill a hole (the width of a pencil) in the top of the plastic, 2-liter bottle cap. If you don't have an electric drill, punch a hole in the cap with a large screw or nail.
3. This next step can be a little tricky. You'll need to put a hole through each of the Mentos just big enough to thread the pipe cleaner.
4. Bend the end of the pipe cleaner to keep the Mentos from falling off. Thread the other end of the pipe cleaner through each of the Mentos.
5. Thread the free end of the pipe cleaner through the bottom of the bottle cap and pull the Mentos tightly against the cap. Bend the end of the pipe cleaner at the point where it comes out of the cap so the Mentos stay in position. It's best to cut the pipe cleaner so that only an inch or so is poking out of the bottle cap.
6. This step is often overlooked... find a large space in the middle of an abandoned field before you move on to the final step. Time for crowd control! Warn the spectators to stand back.
7. Very carefully, replace the cap on the top of the 2-liter bottle and tighten it. Make sure that the Mentos are still tucked snugly into the cap so they don't touch the surface of the diet soda.
8. When you're ready to create the soda geyser, straighten the bend in the pipe cleaner and push it down into the bottle (quickly!). When the Mentos hit the soda, you're in for an incredible show! The bottle shoots like a fire hose because of the restriction of the smaller hole.

Mentos Practical Joke

This little gem creates a squirting bottle of soda the moment anyone opens the bottle... and you don't need to drill any holes in the cap!

1. You'll need a piece of dental floss, a needle and some adult supervision (unless you're already an adult and then you need a kid to play the practical joke on).
2. Thread the dental floss (or thread) through the needle and poke it through the middle of a Mento (the singular form of Mentos). Okay, thread two Mentos if you like (makes it easier to say).
3. Tie the dental floss tightly around the Mentos, leaving one end of the dental floss free.
4. Lower the Mentos tied to the dental floss into the bottle, but don't let them touch the soda. You just want them to hang in the neck of the bottle as close to the top as possible.
   
5. While holding the string in one hand, twist on the cap. Trim the remaining thread that hangs outside the bottle.
6. The bottle is set and ready to be opened... by some unsuspecting test subject. When the cap is twisted open, the Mentos will fall into the soda and there's no stopping the geyser reaction.
   
7. Okay, let's make sure that we stress responsibility. This reaction is going to make a huge mess and that's your responsibility (according to the rules of engagement).

How does it work?

The reason why the soda erupts with such gusto has something to do with the tremendous number of nucleation sites on the porous surface of the Mentos. Nucleation site provides a place for bubbles of carbon dioxide gas to adhere. In this case, the nucleation sites are all over the surface of the breath mints. If enough carbon dioxide molecules gather in one place within a bottle of soda they form a bubble, but these bubbles cannot form without a place to adhere. In other words, the dissolved carbon dioxide gas molecules in the soda make a mad dash for the nucleation sites on the breath mints and form big bubbles that burst out of the liquid.

Additional Info

For a complete discussion of the science behind the gusher, read the Steve Spangler's Mentos Explosion or visit Steve's blog at www.stevespangler.com and enter "Mentos" in the search. Here you'll find the most detailed online discussion of the Mentos Experiment and other tips and tricks from people with too much time on their hands.