As most people know, if you leave ice cream out on the counter, it melts into slush. So how come Liquid Nitrogen can freeze ice cream without a freezer? Also, Nitrogen makes up approximatly 80% of the air, so why don't we freeze?

Nitrogen changes into a liquid at -196 degrees Celciuc. That's -230 degrees Ferenheight! No wonder it freezes everything! Also, Nitrogen's boiling point is so low that, at room temperature, it is constantly boiling and evaporating.