Dry ice is the solid form of carbon dioxide, a gas at standard temperature and pressure with the chemical formula CO2. Its molar mass is 44.0095 grams per mole. Its boiling point is -69.8 degrees Fahrenheit, and its sublimation point is -109.2 degrees Fahrenheit, at a pressure of one atmosphere.
Dry ice is mainly used as a cooling agent. It offers advantages over other cooling agents, including its low sublimation point and the fact that it leaves no residues, apart from frost from water in the atmosphere. Although dry ice itself is not toxic, the carbon dioxide gas resulting from sublimation may build up and cause hypercapnia when handled in closed, unventilated environments.