The Naked Egg

Hide your eyes! The egg is naked. Yes really. Have a go and you’ll see for yourself. Talk about setting a bad egg-zample…

You will need:

2 eggs
500 mL (2 cupfuls) vinegar (and some extra… just in case)
1 clear jar (clean jam jars work) or glass
Clock or timer

What to do:

Being careful not to crack the eggs, carefully place them in the jar or glass.
Pour enough vinegar over the eggs until they are completely covered (if 500 mL of vinegar is not enough, add more until covered).
Watch the eggs for about five minutes. Observe the bubbles of gas that are formed on the surface of the eggs; you'll notice that lots more will appear with time.
Let them sit overnight.
The next day, remove the eggs from the jar or glass and rinse them under a trickle of water in the sink while gently rubbing the shell with your fingers. If the shell does not come off completely, return the eggs to the jar or glass, and try again to rinse them the next day. It may take two or three days to remove the shell completely.
Once the shell is gone, examine the eggs carefully. Hold the eggs up to a bright window or light. You will see the yolk as a dark blob inside. Turn the egg upside down. Can you see the yolk "sinking" to the bottom of the egg?

What’s happening?

Eggshells contain something called "calcium carbonate." This is what makes them hard. Vinegar is an acid known as acetic acid. When calcium carbonate (the shell) and acetic acid (the vinegar) combine, a chemical reaction takes place and carbon dioxide (a gas) is released. This is what the bubbles are made of. The chemical reaction keeps happening until all of the carbon in the shell is used up - this takes about a day. When you take the eggs out of the vinegar, they are soft because all of the carbon escaped out of the shell in those little bubbles. The egg still stays together and doesn't fall apart because it has an "invisible membrane on the surface of it which does not react with the vinegar.

Now you know how to remove the eggshell without breaking it!

For more egg-citing egg-speriments click here.