Radioactive carbon dating game dating site in the uk
The thing that makes this decay process so valuable for determining the age of an object is that each radioactive isotope decays at its own fixed rate, which is expressed in terms of its half-life.
So, if you know the radioactive isotope found in a substance and the isotope's half-life, you can calculate the age of the substance. Well, a simple explanation is that it is the time required for a quantity to fall to half of its starting value.
For example, with potassium-argon dating, we can tell the age of materials that contain potassium because we know that potassium-40 decays into argon-40 with a half-life of 1.3 billion years.
With rubidium-strontium dating, we see that rubidium-87 decays into strontium-87 with a half-life of 50 billion years.
The ratio of the original isotope and its decay product determines how many half-lives have occurred since the sample formed.
A half-life measures the time it takes for one half of a radio isotope's atoms to break down into another element.
This provides a built-in cross-check to more accurately determine the age of the sample.
Plants produce carbon-14 through photosynthesis, while animals and people ingest carbon-14 by eating plants. Scientists determine the ages of once-living things by measuring the amount of carbon-14 in the material.By anyone's standards, 50 billion years is a long time.In fact, this form of dating has been used to date the age of rocks brought back to Earth from the moon.It works because we know the fixed radioactive decay rates of uranium-238, which decays to lead-206, and for uranium-235, which decays to lead-207.So, we start out with two isotopes of uranium that are unstable and radioactive.