You might be asking yourself why you would want to put an egg in a bottle. The answer is, of course, for science! This is a great experiment for explaining the basics of the ideal gas law. Mainly, that gases expand and contract when they change temperature. Here we will explore how to actually do this simple DIY experiment, and what the science is behind it.
Materials:
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Peeled hard boiled eggs. Note that if they crack during peeling, they will likely not survive the ordeal!
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Bottle with a neck smaller than the egg. Erlenmeyer flasks work great!
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Matches, or a small piece of flammable material
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Workspace clear of burning hazards
That’s it!
Doing the experiment:
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Read the steps first. They have to happen quickly!
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Light a match or something small and flammable. A small piece of paper works great!. In the video, we use four strike-anywhere matches.
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Drop your flaming object of choice into the flask. With matches, do it quickly! If you wait too long, there wont be enough fire to heat the air!
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Put the egg on top of the flask so it completely covers the opening. This must be done quickly
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Watch!
You should see the fire go out and the egg get sucked into the bottle shortly thereafter.
What happened?
The fire rapidly heats the air in the flash. Then, the fire should quickly become starved of oxygen and go out. Once the fire stops and the air begins to cool. The molecules in the gas slow down as it cools, decreasing the pressure inside the flask. The air pressure outside is then greater, and pushes the egg down the seemingly-too-small neck of the bottle. Because the air pushes equally from all sides, the egg stays intact, unlike if you had done it with your hand!
How do I get it out?!
There are three good ways to do this.
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Get something pokey, like a butter knife, and chop the egg into bits and dump it out. Messy. Not my favorite.
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Blow in behind the egg. The hot air on your breath should be enough to push it out.
- Flip the flask over so the egg covers the opening from within. Run hot tap water over the base of the flask. As the air inside heats up, it pushes the egg out, simply doing the experiment in reverse!
