Sink or Swim
Bible Verse: All the nations will be gathered before Him, and He will separate them one from another, as a shepherd divides his sheep from the goats. (Matthew 25:32)
Materials Needed:
• Aquarium or deep, clear bowl
• Water
• Assorted unopened soda cans, diet and regular
Bible Lesson
Matthew writes of a future time when those who know the Lord will be selected from all the people of the earth. Scripture is very clear that this day of judgment will come. For the believer this is a great encouragement: someday justice will prevail on the earth. For the unbeliever this promise should be a great motivation to turn to God.
It is impossible for us to judge the motives and hearts of others. We see only the outside of a person, but God looks within the heart and mind. He certainly knows us better than we know ourselves. His judgment is 100 percent accurate and fair.
Science Activity
This activity compares the densities of several kinds of canned soda. The unopened cans are dropped one at a time into the water-filled aquarium. A little showmanship is in order. You could have the audience guess which cans will float or sink as you drop them in.
A pattern will quickly be noticed: cans of diet soda usually float while the others sink. There may be some rare exceptions if a particular can is not completely filled with liquid. The activity is fun and would probably make a good soft drink commercial! It shows how readily the cans can be separated into categories by using the property of density or weight, which is not obvious from the outside appearance.
Cans of diet soda float in water while the sugared variety sinks to the bottom.
Science Explanation
Most diet sodas are sweetened with NutraSweet, also known as aspartame. This artificial sweetener is lighter in weight than the sugar in ordinary soda. Soda cans are not completely filled with liquid; a small amount of carbon dioxide gas is noticeable by the fizzing sound when a soda can is opened. In diet soda, the gas and the aspartame result in a product that is less dense than the aquarium water; therefore the can floats. Meanwhile, the sugared soda is heavier and sinks to the bottom of the aquarium. In a random sample of several cans of soda, I found that the sugared variety averaged 5 percent heavier than the diet.