BASIS OF RADIOCARBON DATING Radiocarbon dating compares the amount of normal carbon with the amount of radioactive carbon in a sample.
However, because it has too many neutrons for the number of protons it contains, it is not a stable atom.
Every 5,730 years, approximately half of this radioactive carbon spontaneously converts itself back into nitrogen by emitting an electron from a neutron.
The carbon dioxide is absorbed by plants, and the plants are eaten by animals, thus contaminating every living thing on earth with radioactive carbon. As time passes, the C14 in its tissues is converted back into nitrogen.
If we know what the original ratios of C14 to C12 were in the organism when it died, and if we know that the sample has not been contaminated by contact with other carbon since its death, we should be able to calculate when it died by its C14 to C12 ratio.
Usually a proton is knocked out of the nitrogen atom's nucleus and is replaced with the neutron.