activity

Have you ever noticed that before you open it, you can’t see any bubbles in a bottle of soda or seltzer? They only appear once you open the bottle and take a drink or pour the liquid into a glass. In this experiment, you’ll learn where those bubbles come from by dropping two different objects—a smooth marble and a rough raisin—into glasses of seltzer and observing what happens.

safety
  • No safety considerations
difficulty
  • Beginner
time
  • 10 minutes

hey curious cook—

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Prepare Ingredients

3 cups (24 ounces)
cold seltzer water
2
raisins or dried cranberries

Gather Equipment

2
tall, clear drinking glasses, both the same size and shape
1
clean marble or ball bearing
Spoon
1
 

Make a prediction: Which glass of seltzer do you think will have more bubbles, the one with the marble or the one with the raisin? Why do you think so?

 
2
 
3 cups (24 ounces)
cold seltzer water

Fill both drinking glasses with cold seltzer until they are about ¾ full (be sure to fill both glasses to the same level).

 
3
 
1
raisin or dried cranberry

Place glasses side by side on counter. Hold marble about 1 inch above surface of seltzer in 1 glass. Hold raisin about 1 inch above surface of seltzer in second glass (make sure marble and raisin are at same height).

 
4
 

Observe your results: Let go of marble and raisin at same time, letting them drop into their respective glasses. Observe what happens for 30 seconds.

 
5
 
1
raisin or dried cranberry

Use spoon to retrieve marble and raisin from glasses. Repeat steps 3 and 4 with marble and second raisin. This time, observe what happens for at least 5 minutes. How do your results compare with your prediction from step 1?