The gas mixes rapidly and becomes evenly distributed throughout the atmosphere the mixing timescale in the order of weeks. Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. The stable isotopes are carbon 12 and carbon The carbon exchange between atmospheric CO 2 and carbonate at the ocean surface is also subject to fractionation, with 14 C in the atmosphere more likely than 12 C to dissolve in the ocean. Beta Analytic. A particle detector then records the number of ions detected in the 14 C stream, but since the volume of 12 C and 13 Cneeded for calibration is too great for individual ion detection, counts are determined by measuring the electric current created in a Faraday cup.
Uses of radioactive isotopes in carbon dating
National Geographic News.
How Does Carbon Dating Work
The accuracy of this proposal was proven by dating a piece of wood from an Ancient Egyptian barge, of whose age was already known. All other atmospheric carbon dioxide comes from young sources—namely land-use changes for example, cutting down a forest in order to create a farm and exchange with the ocean and terrestrial biosphere. Carbon is considered a radioactive isotope of carbon.