When we invited our customers to show us their Summer Science Camps with You Tube videos, Cheryl Purdum when above and beyond the call. Any teacher who is willing to dress up as a Mad Scientist to win a gift certificate to our website clearly deserved that winning title.
Cheryl followed up with us later in the summer to let us know that her summer camp was a huge success. Her pictures were such a treat… I loved looking at the kids’ facial expressions and to truly see a sense of wonder. The color mixing activities looked like they were a big hit, and the cornstarch walk was a riot. Just the look on their faces tells the whole story!
I can’t think of anyone who could have put the gift certificate to better use. Thanks so much, Cheryl, for your enthusiasm for teaching science and for all that you do to create experiences for kids that they’ll never forget.
A few weeks ago on my 9News segment I featured a Seven-Layer Density column. It’s a colorful way to talk about density in the classroom. Well… we thought we had all of our facts straight, but when we inadvertently put in the experiment write-up that oil and water don’t mix because they have different densities, my email box was flooded with concerned teachers, parents, administrators and more, who wanted to set the record straight. Yes, it’s true, oil and water don’t mix because of their intermolecular polarity, not because of density. I love when people actually get involved with the experiments we are posting and care enough about the information to let me know when it isn’t quite up to par.
So, we had our density problem solved, it would seem the Seven-Layer column had experience its fifteen minutes of fame, but, no… this one just wouldn’t die. The day after my news segment, some of our staff noticed that the vegetable oil and rubbing alcohol layers had switched places! Knowing the great response we received before, we opened it up to …
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
Over the years, the exploding pumpkin demo is right up there at the top of my short list for my all time favorite, crowd-pleasing science demonstration. But who wants to wait a whole year just to do the demo again? That’s why we’re working on the fine art of watermelon carving… with the aid of a tiny chemical reaction… okay, it’s an explosion. We just substituted a big, juicy watermelon in place of the pumpkin and pulled the trigger. Since the walls of a watermelon are not necessarily as strong as a pumpkin, sometimes the whole darn thing explodes… but that adds to the fun. Check out the video. (If the video doesn’t play, click on Exploding Watermelon Experiment.)
