Carbon, C,is a chemical element of group IV of the periodic system D. I. Mendeleev, number 6, atomic weight 12,01115. In the nature meets in the form of a diamond, graphite and amorphous coal is the main biogenic element and is included in all organisms, and most products of their decay, the bedrock of the formation of peat, oil, etc., At normal temperatures carbon chemically inert, high - reacts with oxygen (see Monoxide, Carbon dioxide), gray (see carbon Disulfide), metals, hydrogen (see Hydrocarbons). The carbon cycle in nature is connected mainly with living organisms.