How to Make a Folding Egg An extension of the classic Rubber Egg experiment. email to friend
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The Folding Egg activity is actually an extension of the classic Rubber Egg experiment with a really fun twist. Just imagine the look on your friends' faces when you show them an egg and then proceed to fold it in half several times until it forms a small white ball! Wait... it gets better. Just bounce the "folded egg" between your hands and the egg reappears.

Materials

Raw egg
Pin or a thumb tack
Tall glass
Vinegar
Patience

Experiment
Video
Reviews

The first step is the trickiest and requires a little practice. You'll need to blow out the inside of the egg without damaging the egg (too much!). Use a sharp pin, a thumb tack or the tip of a sharp knife (yes, with the help of an adult) to poke a small hole in both ends of the egg. The hole should be about an 1/8 of an inch in diameter. Don't be frustrated if you crack a few eggs before you get the hang of it.
The next step is to scramble the inside of the egg - to break the yellow yolk - and to blow the liquid out through one of the holes. The best way to break the yolk is to poke a long needle or something similar (like a plastic coffee stirrer) through the hole and to carefully poke around in order to break the yolk. Once the yolk is broken and the egg is "scrambled", it's time to blow all of the liquid out of the egg. One method is to clean off one end of the egg, cover the hole with your mouth and blow the egg liquid out the other hole. Of course, it's best to hold the egg over the sink as you're doing this. People who are concerned about using their mouth many experiment with other methods or may elect not to try the activity.
Place the hollow egg in a tall glass or jar and cover the egg with vinegar. You want the egg to be completely submerged in the vinegar which means that you may need to place something on top of the egg to push it down or to try to fill the inside of the egg with vinegar to weight it down. (In the video Steve uses 3 M HCl to speed up the process.)
Leave the egg in the vinegar for about 10 days or until all of the shell has dissolved. What you'll be left with is the translucent membrane of the egg. For the first few days, bubbles of carbon dioxide gas will form on the shell. The vinegar is dissolving with the calcium carbonate in the shell and producing bubbles of carbon dioxide at the same time. When the bubbles stop forming, it's a good indication that the egg shell is completely dissolved.
After 10 days pour off the vinegar and carefully rinse the egg with water. The egg looks translucent because the outside shell is gone! The only thing that remains is the delicate membrane of the egg. You've successfully made an egg without a shell. Okay, you didn't really make the egg the chicken made the egg and you just stripped away the chemical that gives the egg its strength.
Carefully squeeze out all of the water from the egg membrane. Gently blow a little air into one end of the egg and the egg will puff up. Hey, it looks like a real egg! Slowly squeeze the egg in your hand and it will look like you crushed the egg. Drop the egg in a tall, clear glass. Cover the top of the glass with your hand and shake the glass. Air will slowly work it's way into the egg and it will look like the egg magically restored itself.
A Dusting of Baby Powder - That's right... dust the egg membrane with some baby powder (sometimes called Talcum powder). Try to get some of the powder inside the egg as well. The powder will help keep the egg membrane from drying out and cracking - and it makes the egg look even more real.
A Little Magician's Secret - The Folding Egg is a classic science magic trick dating back to the early 1900's. To perform the illusion, the magician would place the inflated egg in an egg carton along with several real eggs. He carefully removed the "special" egg and proceeded to squeeze the egg in his hand. With a little slight of hand, the egg appeared to magically vanish. The magician then showed his audience a clear, empty glass. While showing the glass, he secretly dropped the crumpled up egg membrane into the glass being careful to cover the bottom of the glass with his other hand. "I'll make the egg magically appear by simply shaking the glass." With a little shaking an lots of showmanship, the audience watched as the egg magically reappeared in the glass. That's amazing!