How can isotopes be used in dating archaeological

Archaeologists use the exponential, radioactive decay of carbon 14 to estimate the death dates of organic material.The stable form of carbon is carbon 12 and the radioactive isotope carbon 14 decays over time into nitrogen 14 and other particles.It takes another 5,730 for half of the remainder to decay, and then another 5,730 for half of what's left then to decay and so on.

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At any particular time all living organisms have approximately the same ratio of carbon 12 to carbon 14 in their tissues.It is naturally unstable and so it will spontaneously decay back into N-14 after a period of time.It takes about 5,730 years for half of a sample of radiocarbon to decay back into nitrogen.When an organism dies it ceases to replenish carbon in its tissues and the decay of carbon 14 to nitrogen 14 changes the ratio of carbon 12 to carbon 14.Experts can compare the ratio of carbon 12 to carbon 14 in dead material to the ratio when the organism was alive to estimate the date of its death.

How can isotopes be used in dating archaeological