Background

In this experiment you will use vinegar to dissolve the shell of a raw egg. Vinegar is an acid and egg shells are made from calcium carbonate. Acids react with metal carbonates like calcium carbonate to form salt, water and carbon dioxide gas. The metal carbonate is dissolved in the process. You can find the word equation below.

Acid + Metal carbonate → Salt + Water + Carbon dioxide

You will be able to observe gas bubbles because carbon dioxide gas is formed. We also call this “effervescence”. The egg shell will dissolve leaving behind the raw egg in its membrane.

You will need:

• Vinegar (= acid)
• 1 raw egg
• 1 glass

What to do:

1. Place the raw egg carefully in the glass.
2. Fill the glass with vinegar until the egg floats.
3. Observe what happens on the egg shell. You should see effervescence.
4. Leave your experiment for three days in a cool, safe place.
5. After three days remove the egg from the vinegar and carefully dry it with kitchen roll paper.
6. Take the egg in your hand and squeeze it gently. What does it feel like?

You can watch this experiment on YouTube: