Project Proposal #72

[RogerI...@aol.com]

You've probably seen those YouTube videos, or maybe seen it on MythBusters, where they take some Mentos, drop it into a large bottle of Diet Pepsi (actually, any soda works) and the soda shoots out the top like a geyser. Some even turn them into bottle rockets.

 

Well, I think the haven't gone far enough to explore this interesting phenomenon. I think someone needs to try it out, not just with a measly little liter bottle, but with a 55 gallon drum. Fill it up with soda, have some mechanism to dump in a comparable amount of Mentos, perhaps a nozzle of some sort. And of course film it and post it on YouTube.

 

Seems like a perfect project for makers.

 

- Roger Garrett

 

[Jerry Isdale]

Diet Coke has been experimentally shown to have the best reaction with Mentos.

A large drum would be fun, especially if provided with an appropriate nozzle.

Need to plan for large area cleanup though.

Jerry Isdale

isd...@gmail.com

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[RogerI...@aol.com]

Another idea regarding the Diet Coke / Mentos. The guys on MythBusters did a bunch of experiment to figure out exactly what it was that causes the soda to react so explosively to Mentos. After numerous tests they concluded that it is the deeply pitted surface structure of the Mentos that provides thousands of nucleation sites for the bubbles to form. They concluded this by comparing regular mentos (with the rough surface) to a modified form of Mentos that has a smooth surface. The problem I see with their comparison is that the smooth surface Mentos is smooth because of a wax coating on the candy, not simply because they make the candy itself smooth. Thus, it's still possible that it's something in the candy itself that contributes to the reaction.

 

So, I suggest a better test. Someone should do a casting of a Mentos candy. Make a really high resolution mold from a Mentos. Then cast it in various materials: plastic, aluminum, bronze, etc. Do the same with the smooth-surfaced Mentos. Then do the Diet Coke tests and see whether ANY of them actually produce the geyser effect.

 

- Roger Garrett

 

 

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[Matthew Badeau]

You can get the same reaction from pennies and other objects, although it's nowhere near as dramatic as Mentos. You may be able to take large steel bearing and roll it in sand to get a lot of pitting. (I think I read someone has done this) The sand will have to be very fine... The last place I remember with really fine sand was on Maui. ;)

(Sent from my mobile device.)

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