Definition for radiocarbon dating
The half-life is always the same regardless of how many nuclei you have left, and this very useful property lies at the heart of radiocarbon dating. The graph below shows the decay curve (you may recognize it as an exponential decay) and it shows the amount, or percent, of carbon-14 remaining.
You will notice that after around 40,000 years (or 8 half-lives), the amount left is starting to become very small, less than 1%.
Carbon-14 is a radioactive isotope and is present in all living things in a constant amount.
Radiocarbon dating is a method used to date materials that once exchanged carbon dioxide with the atmosphere; in other words, things that were living.However, once the organism dies, the amount of carbon-14 steadily decreases.By measuring the amount of carbon-14 left in the organism, it's possible to work out how old it is.As a member, you'll also get unlimited access to over 79,000 lessons in math, English, science, history, and more.Plus, get practice tests, quizzes, and personalized coaching to help you succeed.