Final answer:
Carbon-14, also known as radiocarbon, is a radioactive isotope used for radiometric dating of once-living materials, with a maximum effective dating range of up to about 50,000 years. It decays at a known rate after an organism dies, allowing scientists to determine the time since death. Other isotopes like Uranium-238 are used for dating older geological materials.
Step-by-step explanation:
Radioactive Dating Using Carbon-14
Carbon-14 (radiocarbon dating) is a radioactive isotope of carbon that is useful for radiometric dating of materials that were once part of a living organism. Carbon-14 has a half-life of 5730 years and its radioactivity enables scientists to date substances up to about 30,000 years old, and under optimal conditions, up to 50,000 years old. Carbon-14 is produced in the atmosphere through the interaction of solar neutrinos and nitrogen-14 nuclei and is taken up by living organisms. Upon the death of an organism, the exchange of carbon-14 with the environment ceases, and the isotope decays at a known rate, making it possible to calculate the time since death. The carbon-14 dating method has been cross-referenced with other dating methods like historical knowledge and tree-ring counting, confirming its validity and allowing for calibration of the technique.
The ratio of carbon-14 to carbon-12 in a sample can be measured to determine the age of archaeological artifacts, geological formations, and remains of once-living organisms. This method was developed by American chemist Willard Libby, for which he was awarded the Nobel Prize in Chemistry in 1960. Other radioisotopes like Uranium-238 can also be used for dating rocks and are particularly useful for dating very old geological formations.