An egg is put into vinegar for about 48 hours. The vinegar dissolves the eggshell to form CO₂. The egg is still held together by a thin membrane, which lies under the shell. The inside of the egg remains more or less unchanged. Because the membrane does not break like the eggshell, you can gently bounce the egg.

• Olivia J. Mullins, Experimenting with Science: Think, Test, and Learn! (Dummies Junior), 1st Edition John Wiley & Sons, Inc. Hoboken, USA, 2016. ISBN-13: 978-1119291336