# Radioactive dating lab pennies, context for use

Shake the box remember exactly how many times you shook the box so you can do the same thing next time. Scientists continue to investigate atoms and have discovered even smaller constituents of which electrons, neutrons, and protons are made. Radioactive materials contain some nuclei that are stable and other nuclei that are unstable. About coins this can be a mix of pennies, nickels, dimes and others.

## Context for Use

Does the resulting graph have the same shape, or is it different? How do scientists use radioactive decay to date fossils and artifacts? Shows students visually the concepts of exponential decay, half-life and randomness. You will need enough coins I use pennies for each person in the class, some sort of graph paper printed on an overhead, dawson street dating an overhead projector and a pen for the overhead. You might suggest that the students experiment with their graphing results to see if trends begin to form.

## Plz answer my Q

About how many students would have had to sit down if we started with twice as many students? Related Links Radioactive Decay Probability. Isotopes have the same chemical properties, but different physical properties. Students should be able to describe an atom and its basic structure.

Do the number of atoms you start with affect the outcome? This lesson helps students understand the important notion that neutrons in the nucleus add to an atom's mass. Does it form a straight line, or does it have a different shape? Then you will find the number of each type of penny in your mystery sample, general description for using the concepts you developed in the activity.

In the first part of the assessment, students apply what they have learned to various elements. Carbon has a half-life of years, which means that if you take one gram of carbon, half of it will decay in years. It is a great introduction to the scientific process of deducing, forming scientific theories, and communicating with peers. This can set up a good discussion of what is happening to the number of students still standing i. Seeing this connection will help students to understand how scientists can determine the age of a sample by looking at the amount of radioactive material in the sample.

Repeat the activity with different numbers of coins. The most important features of isotopes with respect to general scientific literacy are their nearly identical chemical behavior and their different nuclear stabilities. Background Half-Life If two nuclei have different masses, but the same atomic number, kittens dating those nuclei are considered to be isotopes. Here are links to several variations on this theme.

What do the pennies represent? Shake the bag again and repeat the process. Have the students spill out the candies onto a flat surface.

Is the result a straight or a curved line? Check that all tables and graphs are properly labeled and data is represented correctly. At the end of the lesson, students will be asked to reflect upon and revise, if needed, these definitions.

You may wish to collect these sheets to check for student understanding. You may group students in any size group, but working in pairs involves and engages each student. Wenner, University of Wisconsin-Oshkosh, wenner uwosh. Please contact the author with questions or suggestions. After death, the carbon decays and is not replaced.

## In the Classroom

Record the number of candies you returned to the bag under the next Trial. Have students refer back to their answers to the question in the motivation. As students look at the periodic table, ask them if they see any atomic masses that are whole numbers. This is the first in a three-lesson series about isotopes, radioactive decay, and the nucleus.

- Also, they write a short summary explaining how the lab has illustrated the concepts of isotopes, mass number, and atomic number.
- The demonstration usually takes approximately minutes depending on how long it takes to count the students.
- How is radioactive decay sort of like gambling or playing the lottery?

## Using Popcorn to Simulate Radioactive Decay

## So it is rooted in our experimental The lab procedure to mimic radioactive

Half-Life of Pennyium and replace the nickels that land tail side up with. This experiment is best used by student working in pairs. Science Net Link's Isotopes of Pennies more info. Plot the total results on a graph with number of candies on the vertical axis and trial number on the horizontal axis. Ask them to revise or expand upon their answers based on what they have learned in this lesson.

- Students are able to visualize and model what is meant by the half-life of a reaction.
- By looking at the ratio of carbon to carbon in the sample and comparing it to the ratio in a living organism, it is possible to determine the age of a formerly living thing.
- If students appear to need more instruction on isotopes, you should review these concepts before proceeding with the lab.
- The ratio of the amounts of carbon to carbon in a human is the same as in every other living thing.
- Record both the nickels and the pennies in your data table.
- Carbon is radioactive and undergoes radioactive decay.

Now, look at the numbers you wrote down. Summary A demonstration with full class participation to illustrate radioactive decay by flipping coins. Did each group get the same results? Some of them include handouts to use for homework in smaller classes.

## Half-Life Paper M&M s Pennies or Puzzle Pieces

Students should be able to complete parts A, B, and C in one class period. The half-life of a radioactive isotope refers to the amount of time required for half of a quantity of a radioactive isotope to decay. Do you get exactly the same results each time?

Richards found two atomic masses for lead. How many turns did it take you until there were no coins left? It is a great way to introduce or reinforce the concepts involved in radioactive decay. Did you find this resource helpful?

The rate of decay is a fixed rate called a half-life. Insisting on the rigorous use of isotope and nuclide is probably not worthwhile, and the latter term can be ignored. What about if we only had half as many in this class? In this lesson, pennies of different compositions represent isotopes. It is also useful in the mathematics classroom by the process of graphing the data.

Demonstration of radioactive decay using pennies Jennifer M. **By extension, this experiment is a useful analogy to radioactive decay and carbon dating.** Radioactive Decay Probability. Assessment Ideas Question the student about how this experiment is similar to Carbon Dating. Students can readily understand that pennies of different masses are still pennies.

Electrically neutral particles neutrons in the nucleus add to its mass but do not affect the number of electrons and so have almost no effect on the atom's links to other atoms its chemical behavior. Can you predict which of you is going to be the first to sit down? What happens to the total number of candies with each trial half-life? Set up a place on the board where all students or groups can record their data.