Welcome to Five Minute Science, where we offer up cool science experiments you and your kids can do together using everyday household items, in about five minutes! This week you get to see what kind of pop floats and learn some science too, from the experts at Let's Talk Science.
To show your child how two objects that appear to be the same can have different densities. Be sure to ask your child what he or she thinks might happen before you do the experiment - what result is expected when the regular and diet pop cans are placed in the container of water?
A can of diet pop
A can of regular pop
A deep tub of cold water
Immerse the can of regular pop in a deep tub of cold water. Observe what happens to this can.
Immerse the can of diet pop in a deep tub of cold water. Observe what happens to this can. How does it differ from the can of regular pop?
Explaining the Science:
The regular pop can should have sunk and the diet pop can should have floated. Ask your child why he or she thinks that happened.The scientific explanation is that while both cans are the same size and have the same amount of liquid inside, not all liquids are the same density. Both the regular and the diet pops are mostly water, but the regular pop also contains a significant amount of sugar, usually in the form of corn syrup -- about 40 grams of corn syrup. Diet pop contains artificial sweetener which is much sweeter than corn syrup, so less of it is needed -- about 0.35 grams of sweetener. So the sweetener makes all of the difference. The regular pop is denser due to the 40 grams of corn syrup, which makes it sink. The diet pop is less dense due to the 0.35 grams of sweetener, so it is light enough to float.