There are three naturally occurring isotopes of carbon on Earth: 99 % of the carbon is carbon - 12, 1 % is carbon - 13, and carbon - 14 occurs in trace amounts, i.e., making up about 1 or 1.5 atoms per 10 atoms of the carbon in the atmosphere. Carbon - 12 and carbon - 13 are both stable, while the half - life of carbon - 14 is 5,730 ± 40 years. Carbon - 14 decays into nitrogen - 14 through beta decay. A gram of carbon containing 1 atom of carbon - 14 per 10 atoms will emit 0.2 beta particles per second. The primary natural source of carbon - 14 on Earth is cosmic ray action on nitrogen in the atmosphere, and it is therefore a cosmogenic nuclide. However, open - air nuclear testing between 1955 -- 1980 contributed to this pool.
what type of reaction is the decay of carbon-14
beta decay