Solidifying nitrogen by pumping

A container is filled with liquid nitrogen and placed in a larger contained connected to a vacuum pump. As we start to pump we continuously "steal" the most energetic molecules in the liquid-vapor-equilibrium system, thereby lowering the equilibrium. Since the melting point of nitrogen is not far from the boiling point this method can be used to solidify nitrogen with a relatively basic vacuum pump. In the video we see the nitrogen solidifying and when the pump is turned off it melts again. Since air is mostly nitrogen this is "solid air" (kind of).

Category:

Film & Animation

Tags:

• science

[AdultmentSystem]

what do i need to do this???

[jhekkonen]

1. Liquid nitrogen.

2. An see through air tight container connected to a vacuum pump. The "vacuum" is not very good, I belive it's somthing like a tenth or one percent of normal pressure.

[firemania1567]

cool!

[jhekkonen]

I Tried to explain what happened in the About-section but basically you have liquid nitrogen that freezes, just like water freezes to ice. The method of lowering the temperature is pumping which, in one way of explanation, steals the most energetic molecules from the liquid-vapor system.