Diet Coke and Mentos: Why Do They React?
By Erika R.


Diet Coke Can
The ingredients in Coke are carbonated water, colour (caramel E150d), sweeteners (aspartame, acesulfame-K), flavourings (including caffeine), phosphoric acid, and citric acid. Contains a source of phenylalanine.
Usually carbonation contains a sweetening agent, edible acids, and a natural or artificial flavoring.

Question: Why do Diet Coke and Mentos react?
Answer: Because there are tiny, nucleation sites in the Mentos, which the carbon dioxide in the soda is attracted to, this causes the Diet Coke to explode.

Explanation: The Diet Coke reacts to the Mentos because there are twofold on the Mentos that are tiny pits on the mints surface. Mentos themselves have thousands of these twofold on them that act as nucleation sites, which is what carbon dioxide is attracted to. When the Mentos meet the Diet Coke bubbles form all over the Mentos and quickly rise to the top of the Diet Coke bottle. This is what makes the Diet Coke explode.

Carbon dioxide is pumped into the Diet Coke bottle when sealed. When you regularly open the bottle, it releases the carbon dioxide slowly. When you shake the Diet Coke bottle though, it bubbles. It bubbles because there are tiny nucleation sites on the inside of the bottle so that when you open it, it starts to bubble.


Mint Mentos

The ingredients in Mentos are sugar, wheat glucose syrup, hydrogenated coconut oil, rice starch, gum rabic, sucrose esters of fatty acides, gellan gum, and natural flavors.

My Diagram

Diet Coke and Mentos Diagram Explaining the Steps to Eruption

This is my step by step diagram on what to do when wanted to make the Diet Coke explode.

Nucleation sites: the extreme localized budding of a distinct phase. Example: Gaseous bubbles.
Twofold: twice as great or as numerous; having two parts or aspects. Example: To quit using the computer, it then doesn’t stimulate your brain and it saves you money because you save on internet costs.
Carbon Dioxide: a colorless, odorless, incombustible gas formed during respiration.


Knight, Judson. “Carbon Dioxide.” Science of Everyday Things: Volume 1. Detroit: Gale Group,

2002. Print.

The Nature of Matter

Lewis, Peter. Introducing Physics: Matter, Energy, and Heat. Tucson: Brown Bear Books, 2010.


Spangler, Steve. Unforgettable Experiments That Make Science Fun. Austin: Greenleaf Book Group

Press, 2010. Print

Horton, Patricia, et al. The Nature of Matter. New York: Glencoe McGraw-Hill, 2002. Print.

“Carbon Dioxide." Compton's by Britannica. Encyclopædia Britannica Online School Edition.

Encyclopædia Britannica, Inc., 2011. Web. 23 Sept. 2011.