Freddie's Mystery Cans
Freddie's Mystery Cans


This activity teaches about density and and has something to say about healthy snack choices, too!


To demonstrate that carbonated drinks can have different densities 


  • Large deep container (aquarium works well)
  • Water (to fill the container)
  • Diet cola and regular cola  (12 ounce cans)


Fill the container with water. Discuss the ingredients listed on the cans of diet cola and regular cola with the students. Now ask the question,"Will the cans sink or float when placed into the water?"  After discussing the question, place both cans of cola into the water. What happens?


The regular cola will sink and diet cola will float. Most regular colas have approximately 39 to 41 grams of sugar per can. This is approximately 18 small packets of sugar! Diet colas are sweetened with artificial sweeteners like aspartame®. It takes a small amount of aspartame® ( approximately .35 grams) to create the same "sweetness" of regular cola. Density is the relationship between a substance's mass and the amount of space it occupies (volume). The difference in the weight (mass) of the colas is the reason the regular cola sinks and diet cola floats