Burst a Balloon

PIRA: 4C30.35

A small amount of liquid nitrogen is boiled in a boiling flask with a balloon mounted over the mouth.  As the nitrogen evaporates, the balloon expands until it bursts.  The liquid to gas expansion ratio of nitrogen is about 1:700.  Use this fact to make sure enough liquid nitrogen is used, accounting for the fact that some will be lost as it will boil rapidly until the flask cools sufficiently.  A water bath can be used to greatly increase the boiling rate if you think the balloon is taking too long to fill.