Carbon

Carbon (C), nonmetallic chemical element in Group 14 (IVa) of the periodic table. Although widely distributed in nature, carbon is not particularly plentiful—it makes up only about 0.025 percent of Earth’s crust—yet it forms more compounds than all the other elements combined. In 1961 the isotope carbon-12 was selected to replace oxygen as the standard relative to which the atomic weights of all the other elements are measured. Carbon-14, which is radioactive, is the isotope used in radiocarbon dating and radiolabeling.

The word carbon probably derives from the Latin carbo, meaning variously “coal,” “charcoal,” “ember.” Britanica|carbon

See:

• Carbon dioxide, a greenhouse gas and the main driver of human-caused climate forcing.
• Carbon offsets
• Biochar, a way of sequestering atmospheric carbon and improving soil nutrition.