Have you ever seen raisins dance? This experiment is going to combine what we learned about density and buoyancy over the last couple weeks and make raisins dance so lets get started!
What you need:
- Clear glass
- Colorless soda or club soda
Step 1: Pour the soda into the glass
Step 2: Drop several raisins into the glass
Step 3: Watch the raisins for a bit and they will start to dance!
We just brought raisins to life and made them dance! The raisins sink to the bottom of the glass at first because they are more dense than the soda. Soda is carbonated though which means it has little carbon dioxide bubbles in it which attach on to the rough surface of a raisin. The raisin then gets lifted back to the surface because the bubbles are increasing its buoyancy. When the raisin and bubble reach the surface the bubble pops and causes the raisin to lose buoyancy and sink again. The raisins will keep dancing untl most of the carbon dioxide has escaped and your soda is flat.
Carbonated drinks are made by putting a beverage can under high pressure of carbon dioxide gas. That high pressure causes the carbon dioxide gas to dissolve in the liquid. So when you open a can of pop and hear that sound its actually carbon dioxide gas rushes out. Once the can is open that pressure is decreased and allows that gas to release making the bubbles we see in a soft drink!
We just combined our knowledge of density and buoyancy by making raisins dance! Send our meteorologist Candace Monacelli your pictures doing this experiments at home! She will feature future meteorologists on my Facebook page daily!