Have you tried Diet Coke and Mentos? This activity is so much fun at any age. Students just have a blast.
Why I love Diet Coke and Mentos?
1. It is exciting.
2. It takes simple supplies and creates a great scientific experience.
3. It is great for teaching about the properties of matter. Especially Gases.
4. There is so much science happening.
This activity is so easy. The bottle is opened and 5 to 10 Mentos are quickly dropped into the bottle. Almost immediately a huge geyser of soda erupts. If lucky it can be over 10 feet high.
This is not a chemical reaction, but a physical reaction. Mentos candy contains lots of tiny bumps or nucleation sites. It is also the correct size and weight to cause the carbon dioxide gas to immediately come out of solution. The carbon dioxide grabs onto the nucleation sites on the Mentos and the bubbles get bigger and bigger. These large bubbles force there way out of the bottle with the liquid coming for the ride.
I really like digging into the science of Diet Coke and Mentos. Helping students to understand the science behind it is so much fun. Because it is a physical reaction you don't need to use Mentos. Other objects and candy can be tested. It is all in the nucleation sites. So head to your dollar store for a wide selection of candy to help get started.