Carbon dioxide is a compound made up of the elements carbon and oxygen. Its chemical formula is CO2, which specifies that one molecule of CO2 contains one carbon atom and two oxygen atoms.
Carbon dioxide is a colorless gas found in Earth's atmosphere. Its molecular weight is 44.01 grams per mole, and it is an oxide. Carbon dioxide has a boiling point of -78 degrees Celsius, and a melting point of -56.5 degrees.
Many applications in everyday life, such as in carbonated beverages and fire extinguishers, require carbon dioxide. In its solid phase, carbon dioxide is called dry ice, and is used for the creation of fog in theatrical performances. Carbon dioxide in the atmosphere is also important for the photosynthesis of plants.