Radioactivity half life carbon dating
The different isotopes of carbon do not differ appreciably in their chemical properties.
This resemblance is used in chemical and biological research, in a technique called carbon labeling: carbon-14 atoms can be used to replace nonradioactive carbon, in order to trace chemical and biochemical reactions involving carbon atoms from any given organic compound.
It uses the naturally occurring radioisotope carbon-14 (14C) to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years old.
Carbon has two stable, nonradioactive isotopes: carbon-12 (12C) and carbon-13 (13C).
A useful application of half-lives is radioactive dating.
This has to do with figuring out the age of ancient things.
The carbon-14 isotope would vanish from Earth's atmosphere in less than a million years were it not for the constant influx of cosmic rays interacting with molecules of nitrogen (N) into organic compounds during photosynthesis, the resulting fraction of the isotope 14C in the plant tissue will match the fraction of the isotope in the atmosphere.
After plants die or are consumed by other organisms, the incorporation of all carbon isotopes, including 14C, stops.
It might take a millisecond, or it might take a century. But if you have a large enough sample, a pattern begins to emerge.
Even though it decays into nitrogen, new carbon-14 is always being formed when cosmic rays hit atoms high in the atmosphere.
Plants absorb carbon dioxide from the atmosphere and animals eat plants.
Its existence had been suggested by Franz Kurie in 1934. 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.