British Science Week: How to get an egg in a bottle

Squeeze a hard-boiled egg into a bottle with the help of some smart science

Image credit: Future PLC/ © Illustrations by Ed Crooks

1. Boil the egg

First you need to hard-boil the egg. Getting a raw egg into a bottle would be far too easy! Ask an adult to help you by boiling some water on the stove, then drop in the egg and leave it boiling for at least ten minutes.

Image credit: Future PLC/ © Illustrations by Ed Crooks

2. Peel the shell 

Once your egg has boiled and cooled, take it out of the water and carefully peel off the shell. You should be left with a rubbery egg that’s hard all the way through. If you want to try the experiment a few times, boil more eggs.

Image credit: Future PLC/ © Illustrations by Ed Crooks

3. Use some matches

Next, find a glass bottle with a neck that’s narrower than the egg – it needs to be glass as plastic will melt. Carefully light at least three matches, and drop them into the bottle so that they don’t go out.

Image credit: Future PLC/ © Illustrations by Ed Crooks

4. Act fast

Before the matches burn out, place the egg on the top of the bottle with the wide end up. You don’t need to push it down – just make sure the egg forms a seal around the neck of the bottle.

Image credit: Future PLC/ © Illustrations by Ed Crooks

5. Watch it slide

The egg will start sliding into the bottle as the air pressure inside decreases and pulls it in. As it pops through, a rush of air will fill the bottle again, so the matches will probably go out.

Image credit: Future PLC/ © Illustrations by Ed Crooks

6. Use a candle

You can also use birthday candles. Push two or three into the bottom of the egg, being careful not to break it. Then light them and place the egg on the neck with the bottle on its side.

Summary

When the egg forms a seal on the bottle the matches burn the remaining oxygen then go out. The air in the bottle cools quickly, and the volume of air decreases. This lowers the air pressure and because the air pressure outside is higher, the force overcomes the friction of the egg on the bottle neck and pulls it inside.

Disclaimer: Neither Future Publishing nor its employees can accept any liability for any adverse effects experienced during the course of carrying out these projects or at any time after. Always take care when handling potentially hazardous equipment or when working with electronics and follow the manufacturer’s instructions.
For more fun science activities, download your free British Science Week activity packs here: https://whf.cm/2OrCa3e

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