Nitrogen-Explosion

A PET bottle is filled with liquid nitrogen, sealed, and placed in a 200-Litre barrel. The barrel is then filled to the brim with foam bricks. After about 30 seconds the bottle explodes, ejecting the foam bricks high into the air and across the stage, whilst also realising a white fog.

How does it work?
The liquid nitrogen has a temperature of -196°C. As it heats up it becomes a gas, which directly correlates with an increase in its volume. Due to this increase, the pressure inside the bottle rapidly increases, until it finally bursts and releases a lot of energy.