Where do you get liquid nitrogen?

As of 2014, liquid nitrogen can be purchased commercially from many online retailers, such as Praxair and AirProducts, and it can also be purchased on Amazon. Liquid nitrogen is nitrogen that is held at very low temperatures in order to maintain its liquid state.

One can make liquid nitrogen at home, but in reality, it isn't actual liquid nitrogen, but rather temperature-controlled alcohol. This cryogenic alcohol can be used in chemistry projects just as liquid nitrogen would be used, although it is not intended for use with food.

Liquid nitrogen is used to manufacture ice cream. It is also used in laboratories to preserve blood and tissue samples.