This simple experiment shows how air pressure works. Boiling water in a bottle with a peeled hard-boiled egg on top will condense and the resulting lower air pressure in the bottle will suck the egg inside.
The secret is that as the steam from the boiling water cools, small droplets of water will form on the inside of the bottle. As the gas condenses to liquid, it requires less space in the bottle, so the air pressure drops inside. As it drops, the greater air pressure outside the bottle will try to equalize with that inside the bottle and will push the egg through the mouth of the bottle.
Difficulty: Easy
Time Required: 15 minutes
Here's How:
- Hard boil an egg, peel and set aside.
- Boil water in a pan on the stove or in a glass dish in the microwave.
- Pour the boiling water into a glass bottle with a neck just smaller than the largest diameter of the boiled egg. A baby bottle is usually ideal but others will work as well. Fill the bottle about one-half full.
- Quickly place the egg over the mouth of the bottle.
- Wait a few minutes until the egg is sucked into the bottle.
What You Need
- Boiling water
- Small necked bottle like a baby bottle
- Pot holder for the pan
- A peeled, hard-boiled egg
