On Tuesday, we shared a few of our favorite ways to have fun with bubbles during the summer months. And today, we are letting the bubble fun continue…with these Bubbly Coke + Mentos Experiments!
You know we love a good science experiment, and this one could not get any easier. And even though it’s super simple (and the reaction itself doesn’t last very long), I can guarantee that it will be engaging, exciting, and fun – for the entire family! We certainly spent a lot of time collaborating and laughing while conducting these experiments. π
Science is always more engaging (at least for me) when it produces a noticeable reaction. I want to see the magic happen! And creating a 6-foot geyser of soda is certainly a cool reaction – at least in my book. But we didn’t stop there. Each time we conducted this experiment, our wheels kept spinning, as we tried to come up with new ways that we could manipulate it – ways that we could make it bigger and better, or just different. That’s the beauty of science and creating hypotheses…you keep testing theories until something truly magical happens!
Bubbly Coke + Mentos Experiments
Supplies:
- 2-Liter Bottle of Diet Coke (at room temperature)
- Mentos
- Sheet of Paper & Scotch Tape (optional)
- Latex Balloon (optional)
- Nail/Needle (optional)
We highly recommend conducting this experiment outside, on a flat surface, in a location that you don’t mind getting dirty/sticky (like the side of the street).
Our Initial Attempts (somewhat lackluster, but still fun)
We actually conducted this experiment last year, with a bottle of regular Coca-Cola and a sleeve of Mentos.
When we didn’t get the geyser height we were hoping for, we turned to the internet for some possible answers. We discovered that most people recommend using diet soda, because the aspartame in diet soda lowers the surface tension of the liquid, much more than the sugar or corn syrup found in regular sodas.
So, when we decided to give this little experiment another go, we made sure to purchase Diet Coke instead. We also noticed that you get a bigger reaction if you use more Mentos. The only questions is…how do you get all of the Mentos in the bottle before it starts erupting?
We decided to try wrapping an entire sleeve of Mentos in some mesh drywall tape, so that we could drop the entire sleeve of mint-flavored candy into the bottle at once. We thought that we’d discovered the perfect solution.
But the end result was an even more lackluster reaction than our prior year’s attempt. π What we later discovered is that the Mentos need to go into the bottle freely (not all confined together in the same space). And don’t worry, there is a way to get an entire sleeve of Mentos into the bottle at once, without taping them together. Stay tuned.
Coke + Mentos + Balloons
In the meantime, we decided to try something new and different. If you’ve been following along with a us for a couple of years, you may have seen our Baking Soda & Vinegar Balloon Experiment.Β Our daughter loved this little experiment then…so we decided to give our Coke + Mentos experiment a little balloon twist!
As you can see, there was a whole lot of giggling happening after our balloon exploded and sprayed bubbles everywhere. π We used the exact same concept as our baking soda and vinegar experiment. We shoved the Mentos down into an empty balloon, and then attached the balloon to the top of the soda bottle. The release of carbon dioxide will automatically cause the balloon to start inflating a bit on it’s own, allowing you to easily jiggle the Mentos down into the bottle. But once they’re in there…watch out! That baby can explode in any direction.
We couldn’t let the bubbly balloon fun stop there…so we decided to fill another empty balloon with Mentos. Only this time, my husband decided to poke a few holes in the balloon – to create a little sprinkler of sorts.
And it worked…briefly. π We all started to chuckle as soon as my husband placed the holey balloon over the soda bottle, because it immediately started to squeal. My husband is already thinking of new ways to take this balloon experiment to the next level – he’s busy dreaming up a base to set the soda bottle in (so that the balloon won’t cause it to topple over). And my guess is that he will pop a lot more holes in the balloon next time. Isn’t science fun?
The Ideal Coke + Mentos Geyser
Ok…so I mentioned before that it is possible to get an entire sleeve of Mentos into a bottle of soda (without taping them together) to create a massive Coke + Mentos geyser. How? By creating your own little paper sleeve (mimicking the one that the mint candies come packaged in).
Wrap a sheet of paper around a packaged sleeve of Mentos, until you’ve created a cylinder. Tape the side to secure the cylinder in place. Fold the paper on one end (to close it) and secure it with another piece of tape. Slide the packaged sleeve of Mentos out of the paper cylinder. Unwrap the Mentos, and one-by-one, drop them into your paper cylinder – leaving the top of the cylinder open. Unscrew the lid from the bottle of soda, place a finger on top of the open-end of the paper cylinder, and flip the cylinder upside down (while still holding the candies in with your finger). Line the paper cylinder up with the mouth of the soda bottle, and when you’re ready…release your finger and let the Mentos fall into the bottle. You might also want to take a step back. π
Can you believe how high that geyser went? It was easily over 6-feet in the air. Short-lived…but still AMAZING!
We had so much fun working together…dreaming up different ways to conduct and manipulate this simple Coke + Mentos experiment! And I’m sure it’s won’t be our last attempt.
When all was said and done…we had gone through six 2-liter bottles of Diet Coke, and six sleeves of Mentos…all in a 30-minute time frame. As my husband said, “Our recycling bin makes it look like we suddenly developed a very bad soda habit.” But better to conduct experiments with it, than to actually drink it. π
So, what’s the science behind this magical experiment? There are a few different theories out there, but the most common one has to do with the combination of the carbon dioxide in the soda, and the textured (or dimpled) surface of Mentos candy. Each bottle of soda is full of carbon dioxide (the bubbles). The bubbles stay suspended in the liquid, until you open the bottle and pour the liquid into a glass. When you drop something into a carbonated soda, it speeds up this process by breaking the surface tension of the liquid, and by allowing bubbles to form on the surface of the Mentos. Since Mentos candies are covered in little dimples, it increases the surface area…allowing a larger amount of bubbles to form.
Science is seriously so cool! Have you tried the Coke + Mentos experiment with your kiddos yet?
