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This week's experiment came from a very observant list member named Cheryl.
She noticed something strange about the way condensation forms on drinks.
Materials:
two drinking glasses (not the insulated kind)
ice
water
carbonated soda
paper towel
scissors
Plan:
Be sure that the water and soda are both room temperature. Place both
glasses on a table or flat surface. Put the same number of ice cubes in each glass. Pour water into one glass and the same amount of soda in the other. Let the foam settle down and be sure that the liquid levels are the same. Now, wait a few minutes.
Cut two squares of paper towel, both the same size. When condensation
begins to form, use one square to wipe the outside of the glass of ice water, and the other to wipe the outside of the soda glass. You should notice that the ice water has more condensation than the soda. Why?
If both liquids are the pretty much the same temperature, then why would one glass have more condensation? More condensation tells us that the water
glass is colder, but how can that be if the two liquids are the same
temperature? Look at the inside of the glass of soda. Notice the bubbles that have
formed on the sides. They are bubbles of carbon dioxide formed from the carbonation in the soda. Those bubbles are the answer. They form an
insulating layer between the soda and the glass, keeping the outside of the glass warmer. A warmer surface means less condensation. The difference is not huge, but enough to notice. Especially if you are as observant as Cheryl. When you are finished, be sure to clean up by enjoying the ice water and the soda. From Robert Krampf's Science Education Company To start receiving the Experiment of the Week, just send a blank E-mail to: krampf-subscribe@topica.com | 
