Materials Needed

• Hard-boiled egg
• Jar
• Bottle of vinegar

Procedures

1. Place the hard-boiled egg carefully in the jar. Do not remove the shell.
2. Pour vinegar over the egg until it’s completely covered.
3. Let the egg sit in the vinegar overnight. In the morning take it out, and dry it off.
4. Drop the egg and watch it bounce.

What is Happening?

The vinegar (acetic acid) formed a solution with some of the eggshell. The eggshell is made of calcium carbonate. This leaves the egg with a shell so rubbery it can bounce