The atomic nucleus shown in the top half of this picture is carbon-14. The 14
C nucleus has 6 protons plus 8 neutrons, giving it an atomic mass of 14.
Click on image for full size
Original artwork by Windows to the Universe staff (Randy Russell).
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.
Shop Windows to the Universe Science Store!
Our online store
includes fun classroom activities
for you and your students. Issues of NESTA's quarterly journal, The Earth Scientist
are also full of classroom activities on different topics in Earth and space science!
You might also be interested in:
Carbon-14 dating (also called "radiocarbon dating") is used to determine the age of materials that contain carbon that was originally in living things. It is often used in archeology and some...more
An element (also called a "chemical element") is a substance made up entirely of atoms having the same atomic number; that is, all of the atoms have the same number of protons. Hydrogen, helium, oxygen,...more
Physicists use the term "half-life" to describe how long it takes for radioactive materials to decay. When an atom of a radioactive substance decays, it emits radiation and changes into a different type...more
Some materials are radioactive. They emit radiation. When an atom of a radioactive substance emits radiation, it is transformed to a new type of atom. This process is called radioactive decay. There are...more
Looking for online content that can be used for a climate change education course or module? Pages linked below can be used to support an introductory climate change education for either a unit or a full...more
Atoms and the minute particles from which they are made strongly influence the nature of many phenomena that play out their roles on astronomical scales. The fields of atomic physics and particle physics...more
One main type of radiation, particle radiation, is the result of subatomic particles hurtling at tremendous speeds. Protons, cosmic rays, and alpha and beta particles are some of the most common types...more