So, the fossil is 8,680 years old, meaning the living organism died 8,680 years ago.Learn about different types of radiometric dating, such as carbon dating.Carbon is naturally in all living organisms and is replenished in the tissues by eating other organisms or by breathing air that contains carbon.At any particular time all living organisms have approximately the same ratio of carbon 12 to carbon 14 in their tissues.Radiocarbon dating can be used on samples of bone, cloth, wood and plant fibers.The half-life of a radioactive isotope describes the amount of time that it takes half of the isotope in a sample to decay.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.

If the amount of carbon 14 is halved every 5,730 years, it will not take very long to reach an amount that is too small to analyze.

When finding the age of an organic organism we need to consider the half-life of carbon 14 as well as the rate of decay, which is –0.693.

For example, say a fossil is found that has 35% carbon 14 compared to the living sample. We can use a formula for carbon 14 dating to find the answer.

In the case of radiocarbon dating, the half-life of carbon 14 is 5,730 years.

This half life is a relatively small number, which means that carbon 14 dating is not particularly helpful for very recent deaths and deaths more than 50,000 years ago.

If the amount of carbon 14 is halved every 5,730 years, it will not take very long to reach an amount that is too small to analyze.

When finding the age of an organic organism we need to consider the half-life of carbon 14 as well as the rate of decay, which is –0.693.

For example, say a fossil is found that has 35% carbon 14 compared to the living sample. We can use a formula for carbon 14 dating to find the answer.

In the case of radiocarbon dating, the half-life of carbon 14 is 5,730 years.

This half life is a relatively small number, which means that carbon 14 dating is not particularly helpful for very recent deaths and deaths more than 50,000 years ago.

Understand how decay and half life work to enable radiometric dating.