It’s been called the “vinegar and baking soda” reaction for a new generation. While science teachers have been dropping candies and mints into 2-liter bottles of soda for years in an effort to release all of the dissolved carbon dioxide, the Mentos and Diet Coke reaction became world famous in 2005. Fueled by hundreds of blogs and popular online sharing sites like youtube, this once obscure reaction became an Internet sensation, and the enthusiasm for dropping Mentos into soda continues to grow. Once you get past the initial gee-whiz factor, there’s some amazing science behind a carbonated beverage and a chewy mint.
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Source: Mentos Geyser Experiment | Science Experiments | Steve Spangler Science