Make a Mentos Fountain

[dropcap1]T[/dropcap1]his is the now classic “mentos fountain” experiment with a little twist … use lifesaver candies. Since Lifesavers have a hole in the middle they are just begging to be strung on a paper clip, held in place with a binder clip and then dropped into a 2 liter bottle of soda! Check out the YouTube video at the bottom where we did this with over 360 bottles of Diet Pepsi and nearly 1,800 mint lifesavers.

What you need:

• Binder Clip
• Paper Clip
• Mint LifeSavers
• 2 Liter of Diet Soda at room temperature

This experiment should be done outside in an open area because it can get messy!

What to do:

• Straighten out the paper clip to form a hook.
• String 5 LifeSavers on the paper clip.
• Clamp the end of the paper clip in the binder clip.
• Carefully open the soda bottle without causing too many bubbles.
• Suspend the LifeSavers in the bottle with the binder clip resting on the rim of the bottle.
• Pinch open the clip and RUN.

What’s the science?

Soda (Cola or Pop depending on your location) is a liquid that is supersaturated with carbon dioxide gas. This gas will come out of solution if it’s just given a tiny place to start a bubble. These places where bubbles start are called nucleation sites.

Many things can be a nucleation site, a scratch on the inside of a glass, a speck of dust, a rough spot on a piece of candy. Mentos (as well as lifesavers, sweet tarts, etc.) have a lot of rough spots on their surface that allow bubbles to form. Mentos are also heavy enough to fall to the bottom of the bottle so they interact with lots of soda.

Once the bubbles start to form they grow and more gas starts to come out of solution. In a short amount of time there are so many bubbles formed that the pressure builds up and pushes the soda out of the top of the bottle.

In our experiment we created even more pressure by making use of a pre-drilled bottle cap that restricted the flow of liquid out of the bottle. The smaller the hole, the higher and longer the soda will shoot from the bottle.

We used diet cola since it has no sugar and is a bit easier to clean up. You can use whatever cola you have on hand, just be ready to clean it up afterwards.