🥚 Rubber Egg
Soak a raw egg in vinegar and watch the shell dissolve — leaving a soft, rubbery, see-through egg!
🧰 What you need
Safety note: The egg inside the membrane is still raw. Wash hands after handling. Don't drop it — the membrane can burst!
🔬 Steps
- 1
Gently place the raw egg in the jar. Pour vinegar over it until completely covered.
- 2
Look closely — you should see tiny bubbles forming on the shell immediately. This is the reaction starting!
💡 The bubbles are CO₂ gas being released as the acid dissolves the calcium carbonate. - 3
Seal the jar and leave it for 24 hours. Check on it — the shell will be partially dissolved.
- 4
Pour out the old vinegar and add fresh vinegar. Leave for another 24 hours.
- 5
Carefully remove the egg, rinse it gently with water, and feel it — it's rubbery and slightly see-through!
💡 Hold the egg up to light — you can faintly see the yolk inside! Handle it gently — the membrane can still break.
🧠 The Science
Eggshells are made of calcium carbonate (CaCO₃) — the same material as limestone and chalk. Vinegar contains acetic acid. When acid meets calcium carbonate, a chemical reaction occurs: the calcium carbonate dissolves, releasing carbon dioxide gas (the bubbles you see) and leaving calcium acetate in the vinegar. After two days, the entire hard shell is gone, and only the flexible inner membrane remains — giving you a rubbery, bouncy egg!
📚 Related Lessons
- ⚡ Food for Energy — Food gives us energy, builds our body, and protects us — carbohydrates, proteins, fats, vitamins, and water all have roles!
- 🍊 Vitamins and Minerals — Vitamins A, B, C, D and minerals like calcium and iron are essential for healthy eyes, bones, blood, and immunity!
- 🧼 Food Safety — Washing hands, covering food, and avoiding stale food protects us from germs and food poisoning!