Maryknoll Chemistry -Diet Coke and Mentos

Aaaagh, I can't ever forget my past...my roots have let me grow. I loved teaching because I loved the creativity and working with no boundaries...which probably brought about my end to teaching...because I work best in a job with boundaries. If I'm not given limits, I don't know when to stop working. Gone are the nights and weekends of being trolled up in my house grading and trying to come up with new material...Now, when the clock hits 3 pm, or 11 pm right now...I'm done. I go home, and watch tv...go to a movie...shocking, huh? But then, I look at my pictures and I sigh and ponder the good ole days.

Before, I couldn't post pictures because I am/was a teacher. Ooh, I wonder if I still can't. Oh, well, who you going tell? the police? too bad, I work there. ha ha.

These two photos are from our diet coke and mentos demonstration.

It's a very violent reaction, but there's nothing chemical about it. There is no change in the reactants involved, it is simply a physical reaction. A state of matter change.

All you need:

a 2 Liter bottle of Diet Coke (diet coke is easier to clean up than regular coke)

mentos

A index card

a long cylindrical tube

Notes: The most commonly used solution is coke/diet coke, but any carbonated drink will work. There are two types of mentos, use the mint ones, not the fruity ones. The fruity ones have a layer around it that keeps it from dissolving properly. For our tube, we used a test tube, but you can use a piece of paper or hand. Really you want something that gets the mentos in quickfire without clogging up.

Explanation: As the mentos hits the soft drink, it's outer coating starts to dissolve leaving behind a rough surface. The chemicals in the mentos also triggers a violent release of carbon dioxide. That's the key to this demo. All the carbon dioxide that's in the soda doesn't want to be there, it's held there by pressure. At this instance, it is being set free. As the first molecules of carbon dioxide are released, it changes the balance and all the carbon dioxide molecules change into a gas and spew out the bottle, taking soda with it and making a fountain.

It happens quickly so the faster you get the most mentos in there, the better. Thus the need for something that feeds the mentos one at a time(so they don't clog up) but very quickly. I think we got around 15 mentos in...before the fountain started spitting them out.

Photo 1: Here's C. Mochizuki (one of my favorite last names in my years of teaching) getting ready to pull the index card and drop the mentos in the coke.

PS. I love this picture because of Dexter jumping for joy. He's such a ham. And I notice that he's also wearing a non-Maryknoll sweater. Oooh, he never gave up trying to wear it every day.

So I posted these pictures on flickr so i can get them on my website. I'm getting addicted to checking them out on flickr. This is the second photo that got randomly commented on by a stranger and the second request for someone else to use it. I'm such a dork, I get so excited by that. You must know, I check out my counter website everyday and it's kind of like a popularity contest. I get real bummed when the counter graph goes down. Come one people, make that graph go up. Make my day!!!

PS. I got a root canal today!!! That means my tooth is dead. It sounds so dismal. But it means I can eat ice cream and drink cold milk again. Oh, that sounds delicious.

PSS. Sometimes if you search for your school on youtube.com...you find interesting videos that are obviously made during class. I can even hear my former fellow teachers trying to spread wisdom in the background. Oh, you sly computer-savvy teenagers.