Free 5-day trial Radiometric dating is used to estimate the age of rocks and other objects based on the fixed decay rate of radioactive isotopes.
Learn about half-life and how it is used in different dating methods, such as uranium-lead dating and radiocarbon dating, in this video lesson. As we age, our hair turns gray, our skin wrinkles and our gait slows.
These differing rates of decay help make uranium-lead dating one of the most reliable methods of radiometric dating because they provide two different decay clocks.
This provides a built-in cross-check to more accurately determine the age of the sample.
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.
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.
For example, how do we know that the Iceman, whose frozen body was chipped out of glacial ice in 1991, is 5,300 years old?
Well, we know this because samples of his bones and hair and even his grass boots and leather belongings were subjected to radiocarbon dating.
In general non-scientific terms, isotopes are slightly different types (or "versions") of atoms of the same element. " in GCSE Chemistry, a more detailed answer is required using one of the definitions below The physical properties of isotopes differ because the atomic masses (mass numbers, symbol "A") of isotopes differ.
This affects physical properties such as densities and temperatures of changes of state e.g. There are two common isotopes of the element chlorine. Have you noticed that some versions of the Periodic Table state the mass numbers of the elements as whole numbers only, whereas other versions of the periodic table state mass numbers mean that there are parts of protons or neutrons present in the atom.