Nerdy & Girly Maker Science: Dancing Popcorn
Easy STEM Activity for Kids
First and foremost: Popcorn is delicious, so take this as a sign to buy extra popcorn so you have some to snack on after the science experiment!
This dancing popcorn STEM activity is fun to watch and repeat, changing the ratio of water, vinegar and kernels each time to see how the chemistry affects the popcorn's movement in the cup. Just remember to perform it in an easy-to-clean area in case the cups overflow!
Want to make this activity a little more colorful? Mix 1 tbsp of white vinegar with 20-25 drops of food coloring in a gallon-size bag, then add 1 cup of popcorn kernels, seal the bag and shake it up to coat them. You'll want to give it a day or two before you plan to do the STEM activity to ensure the kernels are dry, mainly to prevent colorful fingertips dyeing everything they touch later on.
Activity Instructions
Ingredients
- 1 mason jar (or other tall glass jar)
- 1 cup water
- 1 tbsp baking soda
- 0.25 cup unpopped popcorn kernels
- 0.5 cup vinegar
Directions
- Pour all of the water (1 cup) into your jar.
- Add all of the baking soda (1 tbsp) to the water.
- Stir the mixture to dissolve.
- Add the popcorn kernels (0.25 cups) into the mixture of water and baking soda.
- Stir again to combine.
- Add the vinegar into your kernel, water and baking soda mixture VERY SLOWLY! (Otherwise you'll create an eruption!)
Pro tip: If you're not seeing an immediate reaction, give everything a quick stir to help activate it.
The Science
When you add these ingredients together, carbon dioxide bubbles are created from the reaction between the baking soda (a "base") and vinegar (an "acid"). These bubbles then attach to the kernels which increases their buoyancy. Once the kernels are covered in enough bubbles, they float to the top!
Then, as the kernels reach the surface, the bubbles pop and release gas into the air. Without all of the carbon dioxide bubbles, the kernels lose buoyancy and sink back down.
This happens again and again as long as the reaction is active, making the kernels appear to "dance" in the jar!