Carbon
Definition and meaning of Carbon in chemistry.
Carbon is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent, meaning it makes four electrons available to form covalent chemical bonds. Carbon is the 15th most abundant element in the Earth's crust and the fourth most abundant element in the universe by mass.
In more detail
The unique ability of carbon to form stable covalent bonds with itself and a wide variety of other elements allows it to form millions of different chemical compounds, forming the basis of all known life. It exists in several allotropic forms, the most common being graphite, diamond, and amorphous carbon. In graphite, carbon atoms are arranged in planar hexagonal networks, making it soft and electrically conductive, whereas in diamond, each atom is tetrahedrally bonded to four others, resulting in extreme hardness. Carbon has an exceptional capacity for catenation, forming long chains and rings that serve as the structural backbone for complex organic molecules like proteins, lipids, and carbohydrates. Carbon undergoes the carbon cycle, transitioning between the atmosphere as carbon dioxide, the biosphere as organic matter, and the lithosphere as fossil fuels. The radiocarbon dating technique relies on the decay of the radioactive carbon-14 isotope to determine the age of organic materials.
Key facts
| Field | Organic Chemistry |
|---|---|
| Formula | C |
| Molar mass | 12.011 g/mol |
| Allotropes | Graphite, diamond, fullerenes |
| Sublimation point | 3642 °C |
Graphene, a single layer of carbon atoms arranged in a two-dimensional honeycomb lattice, exhibits exceptional tensile strength and electrical conductivity.
Frequently asked questions
Why is carbon considered the basis of life?
Carbon can form four stable covalent bonds with other atoms, including other carbon atoms, enabling the creation of complex, diverse, and stable molecules necessary for biological processes.
What are carbon allotropes?
Allotropes are different structural modifications of an element; for carbon, these include diamond, graphite, and fullerenes, which have vastly different physical properties due to their atomic arrangements.