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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.
The atomic nucleus shown in the top half of this picture is carbon-14. The 14C nucleus has 6 protons plus 8 neutrons, giving it an atomic mass of 14.
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Original artwork by Windows to the Universe staff (Randy Russell).

Carbon-14

Carbon-14 is an isotope of the element carbon. All carbon atoms have 6 protons in their nucleus. Most carbon atoms also have 6 neutrons, giving them an atomic mass of 12 ( = 6 protons + 6 neutrons). Carbon-14 atoms have two extra neutrons, giving them a total of 8 neutrons. Carbon-14 has an atomic mass of 14 ( = 6 protons + 8 neutrons). The extra neutrons make the nucleus of carbon-14 unstable. Carbon-14 is radioactive!

Radioactive carbon-14 (also written as 14C) has a half-life of 5,730 years. 14C is used to determine the ages of artifacts that were once living (such as pieces of wood, teeth or bones, coral skeletons, etc.) via a technique called "carbon-14 dating" or "radiocarbon dating".

Some of the carbon dioxide gas in Earth's atmosphere contains 14C atoms. The supply of CO2 molecules which contain carbon-14 is continuously replenished in our atmosphere. Cosmic rays from space sporadically strike nitrogen atoms, converting some common nitrogen-14 atoms into radioactive carbon-14 atoms.

Last modified June 4, 2010 by Randy Russell.

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