углерод

Carbon, C, is a nonmetallic element, grey solid. It is found in nature as graphite (specific gravity2.25), diamond(specific gravity 3.51), and coal (specific gravity 1.88). Carbon is found in all living things, is insoluble in common solvents,and forms an almost infinite numberof organic compounds. Anaturally occurring radioactive isotope,14C, has a half-life of 5780 years and is used in archaeo logical investigations to date artifacts and ancient documents. Other uses of carbon depend on its form. For example, diamonds for jewels and abrasives,graphite for lubricants, activated carbon to absorb color and gases, and wood carbon for fuel are some common examples.