Just like our elephant toothpaste experiment, the naked egg experiment is another classic at-home science activity. With just a few simple ingredients and a little patience, you can give your kids hands-on experience with chemical reactions, osmosis and basic cell structure. You’ll also amaze the kids by making the egg’s shell disappear and transforming it into a rubber-like consistency.
All you’ll need for this experiment are an egg or two (one egg per child is usually a good ratio), white vinegar and a clear container.
Place your eggs in the clear container and cover completely with white vinegar. You’ll immediately notice lots of small bubbles forming. The reaction you’re witnessing is that of the acid (the white vinegar) breaking down the calcium carbonate egg shell into its calcium carbonate parts. The calcium part floats around in the solution while the carbonate part reacts to form the carbon dioxide bubbles.
After letting your eggs soak for 48 hours or so, it’s time to drain the white vinegar and examine your results. The shell will be completely gone and the egg will be slightly larger. This is due to osmosis, or the flow of a liquid (in this case the white vinegar) from one solution through a semi-permeable membrane and into another less concentrated solution.
Let the kids feel the egg’s rubbery membrane, but be careful — once the membrane bursts there’s still a runny, raw egg on the inside that’s been made even more liquidy by the white vinegar that’s seeped into it.
Hold the egg up to light and observe the visible parts of the cell. There’s the membrane on the outside, the nucleus (the yolk) and the cytoplasm (the egg white). Finally, for a more in-depth discussion on cells with the kids, check out Ask a Biologist: The Building Blocks of Life.
Photo Credits: Stephanie Morgan