Egg in a flask

What's this Science Bite about?

Amaze your friends and family with this cool experiment that shows just how powerful pressure can be. Squeeze an egg into a glass jar!

Find out how you get an egg into a glass jar when the neck of the jar is smaller than the diameter of the egg.

Always remember to ask your parent or guardian to help you.

What you'll need

You'll need a flask, a hard boiled egg, some candles and a lighter

  • A hard boiled egg
  • A glass with a wide mouth
  • Birthday cake candles
  • A lighter or a match

How to do the experiment

Follow the instructions in the video below.

Can't see the video above? Watch it on Youtube.

  1. Hard boil an egg - ask an adult to do this for you.

  2. Once the egg has cooled, peel off the shell.

  3. Push the candle into the top of the egg - make sure they will not fall out.

  4. Push the candles into the top of the egg
  5. Ask an adult to light the candles and place the glass over the top.

  6. Ask an adult to light the candles
  7. Hold the egg at the lip of the bottle until the egg holds itself in place

  8. Hold the egg at the lip of the flask
  9. Watch as the egg squeezes through the opening.

    Watch as the egg squeezes through the opening

Find out more...

The candle’s heat warms the air in the flask, because warm air takes up more space it expands and some of it escapes. When the candles go out due to the lack of oxygen, the air inside the glass cools down and contracts. Since some air has escaped the air inside the flask is at a lower pressure on the egg than the air outside the flask. The forces on the egg are unbalanced; the resultant force pushes the egg into the flask and squeezes it through the small opening.

Curriculum links

Forces

SCN2-07a

TripAdvisor

Glasgow Science Centre