Carbon dating nuclear chemistry
Carbon dating is one of the archeology’s mainstream methods for dating organic objects up to 50,000 years old.
This method is based on the idea of radiative decay of Carbon-14 isotopes over thousands of years.
One less abundant form of carbon has atoms that are 14 times as heavy as hydrogen atoms: carbon-14, or 14C, or radiocarbon. At any given moment carbon-14 is decaying in an object, and if that object is living, it is also being replaced at a steady rate.
Carbon- 14 is created when a neutron is excited by a cosmic ray, and then that neutron collides with a nitrogen atom.
Using such methods, scientists determined that the age of the Shroud of Turin (Figure 15.3 “Shroud of Turin”; purported by some to be the burial cloth of Jesus Christ and composed of flax fibres, a type of plant) is about 600–700 y, not 2,000 y as claimed by some.
It is, in fact, leading to the “reconstruction of the history of the world”.
Scientists have concluded that very little change has occurred in the ratio of Carbon-12 to Carbon-14 isotopes in the atmosphere meaning that the relationship between these two should be very similar to how they remain today.
Without radiocarbon dating, “we would still be foundering in a sea of impressions sometime bred of inspired guesswork, but more often of imaginative speculation”.
The carbon isotope is when absorbed by plants through photosynthesis and consumed by animals.
Due to the way the sunlight reacts with the atmosphere, it is also taken in by respiration.