Liquid nitrogen

Liquid nitrogen (also called LN2) is nitrogen in a liquid state. In cryonics, it is used as a cooling agent for cryopatients in their long-term cryopreservation. Nitrogen has a boiling point of about 77 K (−196 °C; −320 °F). Liquid nitrogen is a colorless, low viscosity liquid. It can be produced practically everywhere, since nitrogen comprises 78 percent of Earth's atmosphere.