why would putting mentos mints into a botle fo coke make such an explosion?

Question

why would chocalate mms not have that effect?

Answer 1

You ought to check out the Mythbusters TV show -- I just recently saw an episode where they explained precisely what is happening.

It is a combination of the chemicals used to make the Mentos, the carbonation of the soda, and the surface structure of the mint acting as a whole bunch of nucleation sites for the rapid formation of bubbles. Pretty cool, really.

The chocolate M&Ms do not have the chemicals necessary, and the surface is too smooth.

Here's the summary from the MythBusters Website:

Why does dropping Mentos into a bottle of Diet Coke create a geyser effect?

Mostly because the (uncolored/unglazed version of) Mentos provides nucleation sites for the dissolved carbon dioxide in the Diet Coke to escape as a gas. Other active ingredients in the cascade-effect reaction include aspartame (artificial sweetener), potassium benzoate (preservative), and caffeine in the Diet Coke; and gum arabic and gelatin in the Mentos. The ingredients seem to have a perfect compatibility with each other and, when mixed together and added to the nucleation, creates a chemical reaction that forces the soda to release all of its dissolved carbon dioxide at once, thus causing a more violent eruption than carbonated water alone.

Answer 2

here...check this out...pics and info...

http://www.ocellated.com/2006/09/19/mentos-diet-coke/

http://en.wikipedia.org/wiki/Mentos_eruption

http://www.answers.com/topic/mentos-eruption

http://www.productwiki.com/mentos_mint/article/mentos_diet_coke_fun.html