What you will need:
- A beaker, or a clear glass
- Water
- Popcorn kernels
- Half a cup of white vinegar
- A tablespoon of baking soda
- Optional: Alka Seltzer
What you will do:
- Place your beaker or glass onto a flat surface (like a table). Make sure to clear away any surrounding objects, this may get messy!
- Fill your beaker about half way with water.
- Next, drop in your popcorn kernels (a handful will do).
- Observe, what happens when the popcorn kernels hit the water?
- Did they float or sink? Why is this?
Next, predict what will happen when you add in the white vinegar. Add in the half-cup of white vinegar. Did your prediction come true?
Next, predict what will happen when you add in the baking soda. Add your baking soda.
What did you observe? Did your prediction come true? With all of these ingredients together, bubbles or carbon dioxide are formed and you will notice your popcorn kernels bouncing up and down in the glass or in the beaker.
The bubbles attach themselves to the kernels, allowing the kernel to become lighter than the water, which is why it begins to float up.
However, once the bubbles pop, the weight of the kernel returns to normal and it becomes heavier than water, which is why it heads back down to the bottom until more bubbles form on the kernel again.
Try the experiment with Alka Seltzer, predict, observe, and explain what you see.
