Carbon has the capacity to act chemically both as a metal and as a nonmetal. It is a constituent of all organic matter. Carbon has 13 known isotopes, which have from 2 to 14 neutrons in the nucleus and mass numbers from 8 to 20. Carbon-13 is used as a radioactive tracer. Carbon-14 has been used in the study of such problems as utilization of foods in animal nutrition, catalytic petroleum processes, photosynthesis, and the mechanism of aging in steel.
Compounds There are more carbon compounds than there are compounds of all other elements combined.
The study of carbon compounds, both natural and synthetic, is called organic chemistry. Plastics , foods, textiles , and many other common substances contain carbon. Natural Occurrence and Uses Carbon has been known to humans in its various forms since ancient times. Carbon in the form of diamonds has been found in meteorites. Coke is used as a fuel in the production of iron.