Carbon-14 is commonly talked about as a dating method used to prove that the Earth and fossils are millions or billions of years old. But what exactly is this element? Carbon is the 6th element on the periodic table. It has 6 protons, 6 neutrons, and 6 electrons. When adding together the protons and neutrons, you get a total of 12, and this is referred to as the “atomic mass” of the element. Carbon-12 is the element that you see on the periodic table.
It is stable, unlike Carbon-14, which is radioactive. Instead of having 6 neutrons, Carbon-14 has 8 neutrons, and this makes it radioactive. How did it become radioactive? This occurs in the atmosphere. Cosmic rays come into the atmosphere and produce fast-moving neutrons. These neutrons collide with nitrogen atoms, and this collision results in the creation of Carbon-14. Note: Nitrogen’s atomic mass is 14.
Carbon-14 then arrives to the Earth and is absorbed by plants. Animals eat the plants, consuming both Carbon-14 and Carbon-12, and the radioactive atoms enter into the animal. All living things have Carbon-14 in them, including people, but this doesn’t put us in danger. People and animals take in Carbon-14 until they die.
Carbon-14 dating can only be used to measure the age of things that were once living. It does not measure non-living things such as rock layers. Carbon-14 dating is only accurate to about 80,000 years. Please see the article “What is radiometric dating?” for a continuation of this topic.