Topics: Environment | The Guardian
Carbon (from Latin : carbo "coal") is a chemical element with symbol C and atomic number 6. It is nonmetallic and tetravalent —making four electrons available to form covalent chemical bonds. Three isotopes occur naturally, 12 C and 13 C being stable, while 14 C is a radionuclide , decaying with a half-life of about 5,730 years.  Carbon is one of the few elements known since antiquity. 
Carbon is the 15th most abundant element in the Earth's crust , and the fourth most abundant element in the universe by mass after hydrogen , helium , and oxygen. Carbon's abundance, its unique diversity of organic compounds , and its unusual ability to form polymers at the temperatures commonly encountered on Earth enables this element to serve as a common element of all known life. It is the second most abundant element in the human body by mass (about 18.5%) after oxygen. 
Carbon sublimes in a carbon arc which has a temperature of about 5,800 K (5,530 °C; 9,980 °F). Thus, irrespective of its allotropic form, carbon remains solid at higher temperatures than the highest melting point metals such as tungsten or rhenium. Although thermodynamically prone to oxidation , carbon resists oxidation more effectively than elements such as iron and copper that are weaker reducing agents at room temperature.