experiment is traditionally called the "Egg in the Bottle."
This is a dramatic way of demonstrating the effects of air pressure by
putting a hard boiled egg into a bottle with a small opening and getting
it out in one piece.
Get a boiled egg and remove the shell. Use a
bottle or Erlenmeyer flask where the egg cannot go through the
opening. The air in the bottle has no outlet, it will resist any
pressure on the egg to slip in, unless you change the air pressure
Drop a burning match into the bottle just before
you put the egg on the top of the bottle. When the flame goes out, the
air cools and contracts, forming a vacuum or low pressure. The egg will
fall inside, all by itself. The greater pressure outside the bottle
forces the egg into the bottle.
To get the egg out, you have to change the
pressure again. Turn the bottle upside down so the egg falls into the
neck. Tip back your head and blow vigorously into the inverted bottle.
When you remove your lips, the egg will pop out quickly.