The final word, I hope, on Diet Coke and Mentos
I was up late watching TV and I saw an episode of Mythbusters that I hadn’t seen before. It was done over the summer and it featured, yes you guessed it Diet Coke and Mentos. They answered a lot of the questions surrounding this fun little experiment and clarified for my why the B-day part coke geyser, didn’t geyser.
Okay first thing, it has to be Diet Coke and mint Mentos. I’ll get to the reasons in a second. I did use mint Mentos, but cheepo regular cola for the geyser and that’s why my geyser was a tad whimpy.
The question for the Mythbusters wasn’t if it worked, but how it worked. Clearly it had something to do with CO2 and the candy. So Adam and Jamie compared DC (Diet Coke) and soda water. The DC had a much bigger reaction to a single Mento than soda water, so it must be something other than just candy and CO2.
Adam gathered some of the component parts of DC, Aspartame, caffeine, potassium benzoate, citric acid, and phosphoric acid and tested each one in soda water. Turns out that Aspartame, caffeine, and potassium benzoate all react strongly with Mentos. Ah hah!
So what’s happening to get a ten foot geyser is a cascading reaction with the three components and the Mentos to release a lot of CO2 all at once. Great, but why. Nucleation. Nucleation is, like I’ve talked about before, the reaction between the surface of the object and the liquid to encourage the CO2 out. The rough surface of the candies gives the CO2 something to cling to and then release. Because the candies are heavy they sink to the bottom where they force the reaction in the greatest volume of liquid and giving the CO2 lots of space to push out … and hence the geyser!
So there it is. I need to use Diet Coke so I get the aspertame boost. I need to use mint Mentos for the maximum nucleation sites. I see another geyser in the future …
Oh the picture? That’s Keri Byron who did a spread for FHM on Mythbusters. Yep I think she’s a hottie.
Tags: Diet Coke Mentos, coke geysers, mentos coke, Keri Byron, Mythbusters
7 Comments
Thanks for clearing that up for me, I have been wanting to play that little game myself and I’m glad I didn’t waste a Coke and Mentos by not having the right combination. Oh and the picture? That would have made me pay more attention in physics class.
Yeah it’s amazing how the chemical components work together like that, eh?
Yeah the picture was total eye candy. Gotta love it.
Hi! I am hearing all sorts of different information about cheese to eat during pregnancy. Can you eat Swiss cheese and parmesan? Also is it safe to eat lasagne?
Thanks
I’m not a doctor or expert, but I do remember that my ex-wife was discouraged from eating cheese like brie and camembert. I think the soft cheeses are the problem. Ricotta, (part of lasagne), I don’t know. Your doctor is your best source of information.
Hi,
what exactley about the 3 substances Aspartame, caffeine, and potassium benzoate add to the nucleation process? seeing as nucleation in itself isn’t a chemical reaction, just an accumulation of gasses.
Those substances don’t have anything to do with nucleation, they are reacting with something in the Mentos. So the surface of the Mentos gives the CO2 a place to gather, but it’s the Mentos and those substances that make the CO2 come out of solution.
Yeah i got that, though i guess my question was a little misleading, what i meant to ask was;
do “they” know what exactley happens when these substances react to the Mentos, and to what exactley in the Mentos the substances react? and if they do, what’s the answer?