Radioactive Decay/Half-Life

Sallie M. Fladger John Hope Academy
5515 S. Lowe
Chicago, Illinois 60621


(for grades 3-12)

To demonstrate a model whereby students will perform a hands on application of
determining the half-life of a radioactive element.

Materials Needed:

The following materials are needed for each group of 2-4 students.
1) corn candy 4) paper
2) shoe boxes 5) pencil
3) marker 6) graph paper

Instructors Preparation:

1) Have available shoe boxes for each group of 2-4 students.
2) Using the marker place an X at one end of the shoe box.
3) Place 100 pieces of corn candy in each box.
4) Diagram a model data table showing # of corn candy and # of years.


1) Make a data table as shown and make some predictions.
2) Remove the lid and empty corn candy into box.
3) Close the lid and shake the box gently 5 times.
4) Remove the lid and remove all corn candy with the point
facing the (X) inside of the box.
5) Count & record in the data table the number of corn candy
left after each opening.
6) Repeat steps 3-5 until all of the corn candy is gone.
7) Graph the data from the data table onto graph paper,
showing # of candy corn on the vertical & # of years on
the horizontal.

Expected Results:

Students should discover that after each shake (which represents years) &
the removal of the corn candy (which represents atoms), there is a definite
pattern of decay.

Students discover that it was impossible to predict when or how many corn
candies would decay.


The students' data table and graph curve will determine whether the
students performed the experiment.

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