For this month’s “Yuck @ the Library” science program, I wanted to teach the kids about atoms, molecules, and chemical reactions. Not an easy task for little minds! Molecules and atoms are very abstract subjects and can often be hard to grasp. So I decided to do the “Salty Soda Balloon Experiment“ to illustrate what happens when two different chemical molecules interact (especially under pressure).
– a bottle of coke
– a water balloon
– measuring spoons
This activity requires some hand-eye coordination skills. Consequently, I’d recommend keeping your participants in the 6-12 year old range.
Step 1: The Lesson
With the help of some volunteers, I explained that molecules are made up of atoms and that molecules get “really excited” when they meet other molecules that are different from themselves. I used this information to explain the concept of nucleation sites, which is how the salt latches on to the CO2 in our soda to “ride” up out of the bottle in a fizzy, gaseous, gush!
Step 2: The Demonstration
I carefully had the kids pour salt into their water balloons. Then we went outside, attached our balloons to our Coke bottles, and watched the chemical reactions!