Which isotope of carbon is used in radioactive carbon dating
Scientists call that time its "half-life."Living things constantly replenish the carbon in their bodies, animals from food, plants from the atmosphere, but after death, that process stops.
However, when the organism dies, the amount of c14 declines such that the longer the time since death the lower the levels of c14 in organic tissue.Unlike the other natural isotopes of carbon, carbon-14 is unstable. One of its neutrons turns into a proton and spits out an electron.