Virtual radioactive dating lab
Continue the experiment until only one or 2 people are left (usually 6-7 "half-lives").This can set up a good discussion of what is happening to the number of students still standing (i.e., that the number of isotopes decayed is determined by the initial quantity) and can lead into a discussion of exponential decay, half-life and various other concepts involved in radioactive decay.This activity was selected for the On the Cutting Edge Reviewed Teaching Collection This activity has received positive reviews in a peer review process involving five review categories.The five categories included in the process are 75 students).It is a great way to introduce or reinforce the concepts involved in radioactive decay.
Determine the age of a sample based on the following lab measurements: Total mass of carbon in the sample: 500 mg Activity of sample: 174 decays per hour.
After each "half life", count the people remaining standing and plot it on a piece of graph paper on the overhead.
After about 3 or 4 "half-lives" ask students to predict what's going to happen to the numbers of remaining parent isotopes.
Objective 3240-0501 Model Changes in the earth's surface. Observations: What are the two sides of a penny called?
After the activity students can visit the Virtual Dating web site which allows them to use the mouse to obtain values from the decay curve in answering questions about the amount of radioactive element remaining in a substance.