Carbon 14 dating chemistry
It showed all of Libby’s results lying within a narrow statistical range of the known ages, thus proving the success of radiocarbon dating.Top of page The “Curve of Knowns” compared the known age of historical artifacts associated with the Bible, Pompeii, and Egyptian dynasties with their age as determined by radiocarbon dating.Based on Korff’s estimation that just two neutrons were produced per second per square centimeter of earth’s surface, each forming a carbon-14 atom, Libby calculated a ratio of just one carbon-14 atom per every 10 carbon atoms on earth.
For organic objects of intermediate ages—between a few centuries and several millennia—an age could be estimated by measuring the amount of carbon-14 present in the sample and comparing this against the known half-life of carbon-14.
At the time, no radiation-detecting instrument (such as a Geiger counter) was sensitive enough to detect the small amount of carbon-14 that Libby’s experiments required.
Libby reached out to Aristid von Grosse (1905–1985) of the Houdry Process Corporation who was able to provide a methane sample that had been enriched in carbon-14 and which could be detected by existing tools.
Theoretically, if one could detect the amount of carbon-14 in an object, one could establish that object’s age using the half-life, or rate of decay, of the isotope.
In 1946, Libby proposed this groundbreaking idea in the journal Physical Review.