I first heard about this from a Mark Rober / Nick DiGiovanni video
As the video explains: The science behind this is that the vinegar dissolves the calcium carbonate that makes up the egg shell. He, also, says something about the vinegar diffusing with the egg and causing it to swell, which is what makes it bounce (I have video of that below).
When I did some research in my daughter’s science project book, it said that there is an osmosis happening. The water in the vinegar is absorbed through the egg’s membrane, which makes the egg get larger. I don’t know if that is the diffusing that Mark Rober was talking about, but either way: The egg swells and becomes a bouncy ball.
Though, I wouldn’t recommend bouncing it against a wall in your house like you can with regular bouncy balls.
This is a super fun, super easy science experiment with very little time commitment.
What you need:
- A glass jar. It needs to be big enough to fit the egg inside easily. I used an old pickle jar.
- 1 egg
- A large spoon (optional)
- Vinegar. I used plain white vinegar, but feel free to trial other types and see if you get different results. Ooh! I’m totally going to try using red wine vinegar and see if that changes the color of the egg.
Directions:
Step 1) Carefully set the egg inside the glass jar. Because my daughter’s hand is so small, she was able to grab the egg and set it inside with no trouble. If I had been alone, I might have set the egg on a large spoon, tipped the glass jar until it was almost on its side, and slid the egg off of the spoon into the jar.
Step 2) Add enough vinegar to cover the egg completely. Within minutes, there were bubbles forming around the egg from the vinegar eating away the calcium carbonate.
Step 3) After 24 hours, carefully (CAREFULLY) spoon the egg out of the jar, pour out the vinegar, and replace the vinegar with new. Tilt the jar slightly so you can ease the egg back into the vinegar.
Step 4) After another 24 hours, all that was left of the shell was a thin film that easily rubbed off when I touched it with my finger.
Gently rinse this film off and you’ve got yourself a naked egg!
A bouncy one!
Really bouncy!