By now we are all familiar with the incredible soda pop eruption that happens when Mentos candies are added to Diet Coke. Creating a soda geyser is a must-do science experiment for kids and teachers everywhere. After reading the explanation of the science behind the eruption we were curious about what would happen if we added dry ice to diet soda. As you can see below, the results did not disappoint. This is one of the most thrilling dry ice experiments we have done so far!
*Safety Alert* Dry ice is relatively safe, but it can be dangerous if handled incorrectly. Please see our dry ice safety FAQs for more information about safety, storage, and handling.
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We gathered two supplies for this science experiment:
- Dry ice
- Diet Coke
After the fact, we discovered this really cool geyser tube that has different shaped caps to create different shaped eruptions. Plus, it has a pull pin that gives the brave volunteer a split second longer to get out of the way! We’ll definitely be using a geyser tube next time. We’ll be careful to vent the dry ice and never close it in an airtight container.
My husband used a hatchet to cut off a piece of dry ice that was long and skinny enough to fit through the nozzle of the bottle. We headed outside where we could create a messy explosion without worrying about cleaning it up!
Soda Geyser with Dry Ice
We placed the bottle of Diet Coke on a flat surface and unscrewed the lid. Using gloves, my husband picked up the piece of dry ice, dropped it into the bottle, and ran away as quickly as he could!
The eruption happened immediately and ended up getting on his shoes a little bit. No biggie!
The soda pop easily shot 6 feet into the air. After the eruption the soda left in the bottle continued to fizz and give off dry ice vapor for a couple of minutes.
The Science Behind the Dry Ice Soda Geyser
The science behind this dry ice experiment is essentially the same as that of the Mentos experiment. Steve Spangler explains everything in great detail at the bottom of his post, but I’ll try to explain things more simply.
Basically, little bubbles of carbon dioxide form on the rough surface of the dry ice, a process called nucleation. This pulls the carbon dioxide out of the soda and makes it rush to the surface and escape the bottle. The dry ice is more dense than soda, meaning it sinks to the bottom. The amount of gas and the speed at which it’s released causes an impressive soda geyser eruption!
The two sweetener additives in diet soda are important, too. Aspartame and potassium benzoate make it easier for gas bubbles to form in the soda, causing a faster, more explosive geyser to occur.
Turn this impressive eruption into a full blown science experiment by adding dry ice to many different kinds of soda, varying the size of the dry ice piece added, and varying the temperature of the soda pop. See which combination creates the most impressive soda geyser!