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Radiometric dating lesson activities
"Today we will simulate radioactive decay to understand what we mean by half-life.
Radioactive decay, also known as radioactivity, is the spontaneous emission of radiation from the unstable nucleus of an atom." Have students go to the Isotopes Project website to look for more information about radioactive decay.
Suggest ways that government agencies, such as your state's department of health, might test for strontium-90.To help students understand the history of radioactivity, have them go to Radioactivity: Historical Figures, on the Access Excellence Classic Collection site, to read about the contributions of Wilhelm Roentgen, Antoine Becquerel, Marie and Pierre Curie, and Ernest Rutherford.As students read about these scientists, ask them to think about the following questions: Students can supplement this site with a visit to Isotopes Project.Before the lesson, you will have to weigh out about 80 candies for each group of students.If you count ten and weigh them, then multiply by 8, you will know how many grams of candy to weigh out for each group.If they haven't changed their answers, ask them to explain why.In addition to using answers to students' analysis questions and their graphs for assessment, consider having them respond to the following in their science journals or as a homework assignment: Strontium is chemically similar to calcium.Have them go directly to the Nuclear Structure Systematics Home Page.Once to that page, students should then go to the Isotope Discovery History, a graph of the number of known isotopes versus the date, and to the Chart of Aristotle and Plato (found at the bottom of the page), which the site planners cleverly call "the first chart" of isotopes.To do this lesson and understand half-life and rates of radioactive decay, students should understand ratios and the multiplication of fractions, and be somewhat comfortable with probability.Games with manipulative or computer simulations should help them in getting the idea of how a constant proportional rate of decay is consistent with declining measures that only gradually approach zero.