Radioactive decay
In this activity, students model the radioactive decay process for carbon-14 by flipping coins. Each coin represents a carbon-14 atom, and if it lands tails up when flipped, this indicates radioactive decay.
Radioactive decay
The graph shows a radioactive decay curve for carbon-14. A plot of the activity of the sample versus time shows that the half-life for carbon-14 is 5,730 years.
By the end of this activity, students should be able to:
appreciate the randomness of radioactive decay
describe the concept of half-life
explain the exponential nature of radioactive decay
relate the radioactivity features of half-life, exponential decay and randomness to C-14 dating of artefacts.
Download the Word file (see link below) for:
introduction/background notes
what you need
what to do
student worksheet.
C-14 carbon dating process
Historical artefacts like moa bones can be dated using a technique that measures the activity of the radioisotope carbon-14 still present in the sample. By comparing this with a modern standard, an estimate of the calendar age of the artefact can be made.
To use this interactive, move your mouse or finger over any of the labelled boxes and click to obtain more information.