Carbon (C )
Carbon (C )
Carbon was discovered prehistorically. It is widely distributed in nature and is found in the stars, comets, and the atmospheres of most planets.
Carbon is found free in nature in the forms of graphite, diamond, and fullerenes. A fourth form - 'white' carbon - is also thought to exist. Carbon has seven isotopes, including carbon-12, used as the basis for atomic weights, and carbon-14, which is used to date wood, archaeological specimens, and other materials.
Carbon is found as carbon dioxide in the Earth's atmosphere and dissolves in its natural waters. It is part of rock masses as carbonates of calcium (limestone), magnesium, and iron. Coal, petroleum, and natural gas are chiefly hydrocarbons.