It’s probably the most asked question we get… “How exactly does that experiment with the Mentos and Diet Coke really work?” From the outset (nearly eight years ago), we hypothesized that the exploding soda was a physical reaction, and the key factor in the release of carbon dioxide was the microscopic pits on the surface
of the chewy mint. However, there was no real scientific study that anyone could point to as the definitive answer… until now. In the June issue of the American Journal of Physics, Tonya S. Coffey, an assistant professor of physics and astronomy at Appalachian State University, in Boone, N.C., and her team of fearless physics students reported on the ingredients, temperature dependence, duration, and other parameters of the suddenly famous Mentos-Diet Coke reaction.
There has been considerable debate over gum arabic (found in the coating of the mint) and the role it plays in the physical reaction. Coffey’s group was able to confirm that the surfactant gum arabic is a key component of the reaction: It reduces surface tension, thereby
Everyone in Denver knows Al Lewis, the smart (and funny) business columnist for the Denver Post. If you’re a regular reader, you know that Al looks at things a little differently than most people do. Okay, he’ very funny. My phone rang yesterday and it was Al Lewis - “Hey Steve… any chance I could get you to isolate 9/10th of a cent of gasoline? Ever wonder why they charge us 9/10th of a cent? What could you do with 9/10 of a cent of gasoline?” Sounds like a math problem to me that could maybe turn into a reason to blow something up. I’m in.
So, how much gasoline does 9/10 of a cent get you? The math is pretty straight forward. Let’s say that the price of gasoline is $3.99 9/10 per gallon. Start by dividing 128 ounces (128 ounces = 1 gallon) by 399.9 cents to get the number of ounces per penny. That’s 0.32 ounces per penny. Multiply this by 0.9 to get the number of ounces 9/10th of a cent buy …
Tune into Food Network’s Unwrapped to get a peek inside the Spangler Science labs as Steve shares the science behind the Mentos Geyser all of that exploding soda. Back in December, I mentioned that a crew from Unwrapped on the Food Network wanted to get the real scoop on the popular Mentos and soda reaction. The crew spent an entire day grabbing the reaction from every angle and trying to understand how all of those tiny bubbles produce such a huge fountain of soda. The episode is scheduled to air on September 24, 2007. Consult your local listing for time and channel.
Dropping a roll of Mentos into a bottle of soda used to be something that kids did for fun. Now adults are getting into the act. I opened my e-mail and received these cool pictures from the organizers of the event that took place on July 10th in Flower Mound, TX. Representatives from the Guinness World Records certified the record-setting effort, which went off at 6:30 pm inside the Circle R Ranch Rodeo Arena where 850 independent sales representatives from Books Are Fun, a Reader’s Digest Company, simultaneously dropped Mentos into 850 two-liter bottles of soda using the Geyser Tube Toy. The previous Mentos geyser record was set on May 24, 2007 in Cincinnati, Ohio when 504 Mentos-and-Coke geysers were set off.
Thousands of science teachers found their way to St. Louis for the 2007 National Science Teachers Association convention, and we wanted to make sure they had something to take back to their students. So, we loaded our trucks with experiments and products from the website along with 5,000 rolls of MENTOS stuffed into plastic test tubes and headed for the Gateway City. We were fortunate to have 14 teacher ambassadors from the Hands-on Science Institute join us in the booth to each share their favorite science activities. Aside from 500 bottles of Diet Coke and a mountain of MENTOS, all eyes were on the 18 foot tall soda eruption chamber. We were demonstrating the new Geyser Tube by triggering a MENTOS geyser as fast as we could set-up a launch (about every 2-3 minutes for 3 full days). At the end of the convention, the soda was gone, the rolls of MENTOS were in the hands of 5,000 teachers, the truck was cleaned out… and we all had a blast. It’s back to the classroom for the 14 ambassadors to start working on cool stuff for …
