10 Carbon Facts (Atomic Number 6 or C)

Carbon - The Chemical Basis for Life

Diamond is crystalline carbon. Tetra Images / Getty Images

One of the most important elements for all living things is carbon. Carbon is the element with atomic number 6 and element symbol C. Here are 10 interesting carbon facts for you:

  1. Carbon is the basis for organic chemistry, as it occurs in all living organisms. The simplest organic molecules consist of carbon chemically bonded to hydrogen. Many other common organics also include oxygen, nitrogen, phosphorus, and sulfur.
  2. Carbon is a nonmetal that can bond with itself and many other chemical elements, forming over ten million compounds. Because it forms more compounds than any other element, it is sometimes called the "King of the Elements."
  3. Elemental carbon can take the form of one of the hardest substances (diamond) or one of the softest (graphite).
  4. Carbon is made in the interiors of stars, although it was not produced in the Big Bang. Carbon is made in giant and supergiant stars via the triple-alpha process. In this process, three helium nuclei fuse. When a massive star turns into a supernova, carbon scatters and can be incorporated into next generation stars and planets.
  5. Carbon compounds have limitless uses. In its elemental form, diamond is a gemstone and used for drilling/cutting; graphite is used in pencils, as a lubricant, and to protect against rust; while charcoal is used to remove toxins, tastes, and odors. The isotope Carbon-14 is used in radiocarbon dating.
  1. Carbon has the highest melting/sublimation point of the elements. The melting point of diamond is ~3550°C, with the sublimation point of carbon around 3800°C. If you baked a diamond in an oven or cooked it in a frying pan, it would survive unscathed.
  2. Pure carbon exists free in nature and has been known since prehistoric time. While most elements known since ancient time only exist in one allotrope, pure carbon forms graphite, diamond, and amorphous carbon (soot). The forms look very different from each other and display dissimilar properties. For example, graphite is an electrical conductor while diamond is an insulator. Other forms of carbon include fullerenes, graphene, carbon nanofoam, glassy carbon, and Q-carbon (which is magnetic and fluorescent).
  3. The origin of the name "carbon" comes from the Latin word carbo, for charcoal. The German and French words for charcoal are similar.
  4. Pure carbon is considered non-toxic, although inhalation of fine particles, such as soot, can damage lung tissue. Graphite and charcoal are considered safe enough to eat. While non-toxic to humans, carbon nanoparticles are deadly to fruit flies.
  1. Carbon is the fourth most abundant element in the universe (hydrogen, helium, and oxygen are found in higher amounts, by mass). It is the 15th most abundant element in the Earth's crust.

More Carbon Facts

  • Carbon usually has a valence of +4, which means each carbon atom can form covalent bonds with four other atoms. The +2 oxidation state is also seen in compounds such as carbon monoxide.
  • Three isotopes of carbon occur naturally. Carbon-12 and carbon-13 are stable, while carbon-14 is radioactive, with a half-life of around 5730 years. Carbon-14 is formed in the upper atmosphere when cosmic rays interact with nitrogen. While carbon-14 occurs in the atmosphere and living organisms, it is almost completely absent from rocks. There are 15 known carbon isotopes.
  • Inorganic carbon sources include carbon dioxide, limestone, and dolomite. Organic sources include coal, oil, peat, and methane clathrates.
  • Carbon black was the first pigment used for tattooing. Ötzi the Iceman has carbon tattoos that endured through his life and are still visible 5200 years later.
  • The amount of carbon on Earth is fairly constant. It is transformed from one form to another via the carbon cycle. In the carbon cycle, photosynthetic plants take carbon from air or sea water and convert it into glucose and other organic compounds via the Calvin cycle of photosynthesis. Animals eat some of the biomass and exhale carbon dioxide, returning carbon to the atmosphere.


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