'A Soda and Candy eruption (also known as a Coke and Mentos eruption or a geyser) is a reaction of carbonated beverage and Mentos candies. The numerous small pores on the candy's surface catalyze the release of carbon dioxide (CO2) gas from the soda, resulting in the rapid expulsion of copious amounts of foam. When the candies come into contact with the liquid, a reaction causes the formation of foam at a rapid rate. A 2006 episode of the television show Mythbusters concluded that the potassium benzoate, aspartame, and CO2 gas contained in the Diet Coke, in combination with the gelatin and gum arabic ingredients of the Mentos, all contribute to formation of the foam. The structure of the Mentos is the most significant cause of the eruption due to nucleation. Mythbusters reported that when fruit-flavored Mentos with a smooth waxy coating were tested in carbonated drink there was hardly a reaction, whereas mint-flavored Mentos (with no such coating) added to carbonated drink formed an energetic eruption, affirming the nucleation-site theory.'

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