One of the best ways to get kids excited about science is through science experiments. When it comes to science activities for kids, this Mentos and soda pop geyser is one that your children will never forget.
This soda pop experiment is best done outdoors, preferably in a grassy area. You can use either regular cola or diet cola for this experiment. Diet cola is often chosen because it is less sticky and therefore easier to clean up. It also has the most explosive reaction. Brand doesn’t matter a lot, so feel free to buy a cheaper brand, which is helpful if you want to do the experiment several times. (Trust me, your kids will want to do it again.)
How to Make Your Own Soda Pop Geyser
Get out 7 of the mints (half the package) and line them up so they are touching each other. Pull off just enough tape and secure one side of the mints to the tape. This will enable you to get all the mints into the cola quickly, while still leaving enough surface area of the mints for the experiment to work. (You can also buy this special Geyser Tube to help get the Mentos in all at one time.)
Once your mints are ready, carefully open the bottle of soda pop. Try not to shake it, as this will reduce the effects of the experiment. Position the bottle firmly on the ground so it won’t tip over.
Drop the tape holding your mints into the cola and quickly back away. Watch the amazing soda pop eruption!
So, why does the experiment work?
Carbon dioxide is pumped into pop bottles at the factory. This is what causes bubbles to rise to the surface when you first open the soda. Mentos actually have tiny pits all over the surface. These pits are the perfect place for those little carbon dioxide bubbles from the cola to collect. Since the Mentos are heavy, they quickly sink to the bottom of the bottle. Eventually all those little air bubbles that collect on the candy work to push the cola up and out of the bottle in a dramatic way.
Try measuring how high the explosion reaches. Mark distances with sidewalk chalk or tape on an outdoor wall and place your bottle against the wall to see how high it goes.
Determine whether temperature affects the results. Try it with a cold bottle of soda and a warm bottle.
Experiment to find out which type of soda pop has the biggest reaction. Try cola, diet cola, orange, and a clear soda pop.
Experiment with the Mentos candies used. Do you get a bigger reaction if you use more Mentos? What if you use a different flavor of Mentos?
Making things explode is definitely one of my son’s favorite types of science experiments. Luckily I planned ahead and had enough materials to do the soda pop and Mentos geyser several times. It was definitely a huge hit!
Other kids science experiments you may like: