Experimenting with a naked egg is the perfect kitchen science experiment to teach kids a how the cells in their body work. Kids will get an inside look into a raw egg by using common kitchen supplies to dissolve the shell right off of it! Then they will experiment with the naked egg to see how it changes in various solutions.
Safety Alert: Always make sure to wash your hands after handling raw eggs.
Making a Naked Egg
*This post contains affiliate links. Please see our disclosure policy.
We headed into the kitchen to gather the following supplies:
- Food Coloring (optional)
- Different clear liquids (corn syrup, carbonated water, clear soda, salt water, sugar water, soapy water, etc.)
To make our naked egg we followed these directions:
- Immerse each egg in a cup of vinegar. We started out with four eggs, each in their own cup of vinegar. I’m glad we did four, because one accidentally broke, but we still had three to experiment with! The egg will float at the top and a bit will hover above the surface of the vinegar, which is just fine.
- Place the cups in the refrigerator. After about 24 hours check to see if the egg shell has completely dissolved. If not, drain the vinegar and add some fresh vinegar to each cup. You can even add 10 drops of food coloring per cup if you want a brilliantly colored naked egg!
We observed bubbles on the surface of the eggshell almost immediately. Those bubbles are carbon dioxide gas forming due to the reaction between vinegar (which is acidic) and the calcium carbonate egg shell. (Take a look at this amazing color changing fizzy reaction or the explosive film canister rockets to see other examples of an acid reacting with a base!) Over time the vinegar will completely dissolve the entire egg shell.
Exploring the Naked Egg
Once we had our colorful naked eggs we experimented to see what would happen when we put them into other liquids besides vinegar. We chose to use salt water, Sprite, and corn syrup, since we had those on hand.
We placed our eggs in their respective liquids, labeled each jar, and left them in the refrigerator for another day. The first thing that impressed me was how fast the color from the egg in salt water leached out! Why do you think this happened?
The results were pretty cool. We ended up with two plump eggs and one egg that my three-year-old said “went flat”. The red dehydrated egg was the one we put into the corn syrup.
The Science Behind the Naked Egg Experiment
The membrane of a cell (in this case, the egg) is semipermeable, meaning that small particles can go in and out of the cell while large particles stay out. Water and other nutrients (and food coloring) are small enough to travel in and out of the cell. When the concentration of water in the cell is different than the concentration of water outside of the cell, the water will move either in or out of the cell to balance the concentration inside and out. This is called osmosis.
Osmosis explains why the egg in the corn syrup shriveled up. Corn syrup has a very low concentration of water in it so some of the water from the inside of the egg traveled through the membrane into the corn syrup, making the egg cell shrink.
We learned that salt water and sugary soda have similar water concentrations as the inside of the egg since those two eggs stayed plump!
I took this experiment one step further, just to fulfill my own curiosity. I placed the red egg (the one that got dehydrated in corn syrup) into a cup full of water for another day. What do you think happened? (I’ll tell you…it plumped right back up as water from the cup traveled back into the egg via osmosis. So cool!)
The Curious Kid’s Science Book
This experiment is one of over 100 from Asia Citro’s new book, The Curious Kid’s Science Book. She is the author of the blog Fun at Home With Kids, which is full of unique, colorful, educational, and safe activities for kids. If you enjoyed this experiment you will LOVE the other 100+ experiments in The Curious Kid’s Science Book.