Radioactive decay is a natural process and comes from the atomic nucleus becoming unstable and releasing bits and pieces.
These are released as radioactive particles (there are many types).
those that form during chemical reactions without breaking down).
The unstable or more commonly known radioactive isotopes break down by radioactive decay into other isotopes.
Only a tiny percentage of carbon atoms are carbon-14. Figure below shows carbon dioxide, which forms in the atmosphere from carbon-14 and oxygen.
For example, the half-life of carbon-14 is 5730 years. Over the next 5730 years, half of the remaining amount will decay. How many grams will there be in another 5730 years?
Here is an easy-to understand analogy for your students: relative age dating is like saying that your grandfather is older than you.
This radioactivity can be used for dating, since a radioactive 'parent' element decays into a stable 'daughter' element at a constant rate.
An element is defined by the number of protons it contains. For carbon-14 decay, each carbon-14 atom loses an alpha particle. This is illustrated in Figure below and at the link below.[Insert a link to an animation of the decay of carbon-14 to nitrogen-14.] The decay of an unstable isotope to a stable element occurs at a constant rate. The decay rate is measured in a unit called the half-life.
All atoms of a given element contain the same number of protons. Atoms of an element with different numbers of neutrons are called isotopes. The half-life is the time it takes for half of a given amount of an isotope to decay.
Relative age dating also means paying attention to crosscutting relationships.
Say for example that a volcanic dike, or a fault, cuts across several sedimentary layers, or maybe through another volcanic rock type.