Radioactive dating u 238
Elements that emit ionizing radiation are called radionuclides.When it decays, a radionuclide transforms into a different atom - a decay product.Elements in the periodic table can take on several forms.Some of these forms are stable; other forms are unstable.
There are some elements with no stable form that are always radioactive, such as uranium.
All radioactive dating is based on the fact that a radioactive substance, through its characteristic disintegration, eventually transmutes into a stable nuclide.
When the rate of decay of a radioactive substance is known, the age of a specimen can be determined from the relative proportions of the remaining radioactive material and the product of its decay.
This method is also very limited because uranium is not found in every old rock.
It is rarely found in sedimentary or metamorphic rocks, and is not found in all igneous rocks.