Carbon is a radioactive isotope of carbon, containing 6 protons and 8 neutrons, that is present in the earth's atmosphere in extremely low concentrations. It is naturally produced in the atmosphere by cosmic rays and also artificially by nuclear weapons , and continually decays via nuclear processes into stable nitrogen atoms. Suppose we have a sample of a substance containing some carbon Suppose our sample initially contains nanograms of carbon
5.7: Calculating Half-Life
Understanding units and unit conversions | Radiocarbon Collaborative
The ratio of carbon to carbon at the moment of death is the same as every other living thing, but the carbon decays and is not replaced. The carbon decays with its half-life of 5, years, while the amount of carbon remains constant in the sample. By looking at the ratio of carbon to carbon in the sample and comparing it to the ratio in a living organism, it is possible to determine the age of a formerly living thing fairly precisely. So, if you had a fossil that had 10 percent carbon compared to a living sample, then that fossil would be:.
When we speak of the element Carbon, we most often refer to the most naturally abundant stable isotope 12 C. Although 12 C is definitely essential to life, its unstable sister isotope 14 C has become of extreme importance to the science world. Radiocarbon Dating is the process of determining the age of a sample by examining the amount of 14 C remaining against the known half-life, 5, years.
Unstable nuclei decay. However, some nuclides decay faster than others. For example, radium and polonium, discovered by Marie and Pierre Curie, decay faster than uranium.