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Soda Geyser

Soda Geyser

I’m so excited to share this week’s Simple Science experiment.  This Soda Geyser is one of my all-time favorite science experiments to do with my boys.  It involves something exploding so of course it is right up their alley!  My boys would have watched this experiment all day if we had an unlimited amount of soda and Mentos.

Supplies needed:

  • Diet Soda (Make sure to purchase several bottles to keep the fun going.
  • Mentos (mint flavored)
  • Geyser Tube (this is totally optional but makes the experiment SO much easier and a lot more fun.

This experiment is quite simple, especially if you are using the geyser tube.  Find area that you won’t mind getting sticky and set up a 2 liter bottle of Diet Soda.  Add 4-6 Mentos and step back to enjoy the geyser.  It’s that simple.  The nice thing about the Geyser tube is that you can add the Mentos before hand and then twist the tube onto your soda.  When you are ready, you can just turn a knob that allows for the Mentos to fall in all at once instead of trying to rush to get as many in as possible by hand before it explodes.

Soda GeyserMake sure you are using Diet soda.  We did a little experiment with different types of soda and found that the ones with the highest amount of sugar, put out the weakest geyser and the diet soda was by far the best geyser.

So how does this all work?  What makes the geyser?  Well, the verdict is still out on that one.  I’ve seen several explanations around the web on how and why it works but this explanation by Steve Spangler is probably the best:

“Each Mentos candy has thousands of tiny pits all over the surface. These tiny pits are called nucleation sites – perfect places for carbon dioxide bubbles to form. As soon as the Mentos hit the soda, bubbles form all over the surface of the candy. Couple this with the fact that the Mentos candies are heavy and sink to the bottom of the bottle and you’ve got a double-whammy. When all this gas is released, it literally pushes all of the liquid up and out of the bottle in an incredible soda blast.” – See more at:

And it’s time for another Saturday Science Blog Hop!  I love checking out these fun experiments each week.


Hop on over and check out these fun experiments from some of my favorite bloggers and then link up your Science projects below.

Air Pressure from Suzy Homeschooler

What is soil? Experiments and activities for kids from The Usual Mayhem

Learning about nature with toddlers and preschoolers from P is for Preschooler

Preschool Books about Recycling from Stir the Wonder

Engineering Egg Drop Project from Lemon Lime Adventures