The Fall 2009 issue of The Old Schoolhouse Magazine has a really great article on page 102 by Dr. Jay Wile detailing how to do a very complete experiment making soda fountains and a nice commentary on why it works. It just so happens that doing that experiment fits nicely with the science experiments we are in the process of doing so I decided to do it. It ended up being probably the best science experiment we have ever done!
First we did the control. We knew that Diet Coke and Mentos would produce a nice fountain. We’ve seen videos of people doing it, though we had never done it ourselves. The resulting fountain was quite a nice one.
Next we tried Mentos in cold Diet Coke. The resulting fountain was good, but not great.
Then we tried Mentos in regular Coke. The fountain was a little less than the cold Diet Coke.
Next we tried Mentos in Diet Dr. Pepper (or, rather, Diet Dr. Perky since Ani insisted on using the exactly correct name – it’s generic Diet Dr. Pepper). The fountain was better than the cold Diet Coke, but nowhere near as good as the room temperature Diet Coke.
Then we tried Mentos in regular Dr. Pepper. The resulting fountain was quite similar to the regular Coke.
Next we tried mint LifeSavers in Diet Coke. The fountain wasn’t impressive at all.
Next we put salt into Diet Coke. We were all surprised that it made a fountain, though it was a small one. The kids had tried the remaining soda for each of experiments and Cameron had even discovered the smaller fountains were great for leaning over and drinking right from the bottle. Even though they were varying degrees of flat, he enjoyed all of them. Drinking the fountain from the salt in Diet Coke bottle proved to be absolutely disgusting, however.
The little boys very much enjoyed watching the fountains. Adrian kept wanting to drop a rock into a bottle. After all, the big kids were putting something in them, so why shouldn’t he?
After we cleaned up, we sat down and talked about exactly why the experiments worked the way they did. The kids were fascinated. Finally, we went on youtube on the TV and watched a couple videos from EepyBird.com.