Description
Students experience the phenomenon of radioactive decay through observing tracks created in a cloud chamber by ionizing radiation as it passes through a cooled, supersaturated alcohol vapor. They illustrate and explain what is happening in the cloud chamber on a particulate level while learning about radioactive decay and writing nuclear equations to model that decay. Students then connect the phenomenon to real-world applications such as nuclear power, nuclear medicine, and archeological dating.
Time Requirement
Total, 55 minutes. Teacher prep, 15 minutes. Demonstration and discussion, 40 minutes.
Digital Resources
Includes 1-year access to digital resources that support 3-dimensional instruction for NGSS. Digital resources may include a teacher manual and student guide, pre-lab activities and setup videos, phenomenon videos, simulations, and post-lab analysis and assessments.
Crosscutting Concepts
Energy and Matter
Disciplinary Core Ideas
PS1.C: Nuclear Processes
Science and Engineering Practices
Developing and Using Models
Learning Objectives
- Model radioactive decay by writing nuclear equations for alpha, beta, and gamma emissions.
- Explain how design features of the cloud chamber allow for observing subatomic particles.
- Illustrate and explain what happens in the cloud chamber on a particulate level.
Prerequisite Knowledge and Skills
Students should be familiar with models of atoms, subatomic particle arrangement, and isotopes; writing balanced nuclear equations; and how charged particles interact with each other in electric and magnetic fields.