Liquid nitrogen is the liquefied form of the element nitrogen that is commercially produced by fractional distillation of liquid air. Like nitrogen gas, it consists of two nitrogen atoms sharing covalent bonds (N2).
Liquid Nitrogen is safe when handled correctly. It is non-toxic, odourless, and colourless. It is relatively inert. It is not flammable.
Liquid nitrogen is stored in special insulated containers that are vented to prevent pressure build-up. Depending on the design of the dewar or flask, it can be stored for hours up to a few weeks.
Nitrogen is in a liquid state when at a very low temperature. Liquid nitrogen boils at 77 kelvin (−196 °C, −321 °F). LN2 displays the Leidenfrost effect, which means it boils so rapidly, it surrounds surfaces with an insulating layer of nitrogen gas. This is why spilled nitrogen droplets skitter across a floor.