What you need:
- One boiled egg
- White vinegar
- Large bowl
How to:
- Place the boiled egg in the bowl.
- Completely cover the boiled egg with vinegar.
- After three days, remove the egg from the jar
- Gently rinse the shell off the egg with tap water.
How does the egg feel? Rubbery? Try bouncing the egg on a hard
surface. Get your friends to have a go. Who can get the egg to
bounce highest?
You can make a coloured bouncy egg by adding food colouring to
the vinegar.
Or, you can soak raw eggs in vinegar, with a similar result.
Don't bounce raw eggs though - they might pop!
How does it work?
Egg shell is made of calcium carbonate. Vinegar
is an acid - acetic acid. When calcium carbonate
is exposed to an acid it reacts. The calcium carbonate egg shell
dissolves, but the membrane inside the shell, surrounding the egg,
remains intact. This makes the egg feel rubbery.
This video shows you how to make a rubbery raw egg: