Experiment 2

Buoyancy and Pressure

 

In this experiment you will find out if Ms. Crowler was telling the truth by observing and comparing the behavior of raisins submerged in tap water with raisins submerged in carbonated water (soda pop) over time.

I. Hypothesis Bubbles in the carbonated water will cause wrinkled fruit such as suckelberries or raisins to rise and fall (dance).

II. Materials needed

  • a can or bottle of carbonated water or clear soda (fizzy drink) like 7-Up™ or Sprite™
  • 2 tall, clear glasses or plastic cups
  • 12 or more raisins (fresh raisins work the best)
  • a glass of tap water

Dancing Raisins in Beaker

III. Procedure/Observation

  1. Fill one glass with tap water and fill the other glass with carbonated water or clear soda.
  2. Drop 6 or 7 raisins into the glass of tap water and drop six or seven raisins into the glass of carbonated water or soda.
  3. Watch the raisins for a few seconds. Describe what is happening to the raisins. Do they sink or float? Do you notice any difference in how the raisins behave in the tap compared to the carbonated water or soda? Keep watching. What happens in the next several minutes?

 

 


 

V. The Fizz in Suckelberry Soda
Carbonated beverages are prepared by putting the beverage into a can or bottle under high pressure with carbon dioxide gas. The high pressure causes the carbon dioxide gas to dissolve in the liquid. When the can or bottle is opened the pressure inside the can decreases allowing some of the carbon dioxide gas dissolved in the liquid to escape as bubbles.