ALEX Learning Activity


Radioactive Half-Life

A Learning Activity is a strategy a teacher chooses to actively engage students in learning a concept or skill using a digital tool/resource.

You may save this Learning Activity to your hard drive as an .html file by selecting “File”,then “Save As” from your browser’s pull down menu. The file name extension must be .html.
  This learning activity provided by:  
Author: Nancy Caffee
System:Blount County
School:Blount County Career Technical Center
  General Activity Information  
Activity ID: 2120
Radioactive Half-Life
Digital Tool/Resource:
Virtual Lab: How can you simulate the half-life of a radioactive element?
Web Address – URL:

In this virtual lab, students simulate the radioactive half-life of four different elements. They record the data in a digital table, graph the data, and then answer journal questions based on their findings. 

This activity was created as a result of the ALEX Gap Project Resource Development Summit.

  Associated Standards and Objectives  
Content Standard(s):
SC2015 (2015)
Grade: 9-12
Physical Science
6 ) Develop models to illustrate the concept of half-life for radioactive decay.

a. Research and communicate information about types of naturally occurring radiation and their properties.

b. Develop arguments for and against nuclear power generation compared to other types of power generation.

NAEP Framework
NAEP Statement::
P12.11: Fission and fusion are reactions involving changes in the nuclei of atoms. Fission is the splitting of a large nucleus into smaller nuclei and particles. Fusion involves joining two relatively light nuclei at extremely high temperature and pressure. Fusion is the process responsible for the energy of the Sun and other stars.

NAEP Statement::
P12.15: Nuclear reactions (fission and fusion) convert very small amounts of matter into appreciable amounts of energy.

Unpacked Content
Scientific And Engineering Practices:
Developing and Using Models; Engaging in Argument from Evidence; Obtaining, Evaluating, and Communicating Information
Crosscutting Concepts: Systems and System Models; Energy and Matter
Disciplinary Core Idea: Matter and Its Interactions
Evidence Of Student Attainment:
  • Research and analyze science texts for radioactivity.
  • Communicate information obtained from various sources about types of naturally occurring radiation and their properties.
  • Engage in argument from evidence obtained from various sources for and against nuclear power generation compared to other types of power generation.
  • Develop and use a model to illustrate the concept of half-life for radioactive decay.
Teacher Vocabulary:
  • Atom
  • Isotopes
  • Protons
  • Neutrons
  • Electrons
  • Radioactivity
  • Half-life
  • Radioactive decay
  • Alpha particles
  • Beta particles
  • Positrons
  • Gamma
  • Fission
  • Fusion
  • Kinetic energy
  • Electromagnetic radiation
  • Emission
  • Nuclear power
  • Hydroelectric power
  • Solar power
  • Wind power
  • Penetrability
  • Fossil fuel combustion
  • Decay series
Students know:
  • The atom is made of protons, neutrons, electrons.
  • The types of radioactive decay include alpha, beta, and gamma.
Students are able to:
  • Exemplify the radioactive decay of unstable nuclei using the concept of half-life.
  • Perform simple half-life calculations based on an isotope's half-life value, time of decay, and/or amount of substance.
  • Cite specific textual evidence to support analysis of science and technical texts attending to the precise details of explanations or descriptions.
  • Determine the central ideas or conclusions of a text; trace the explanation or depiction of a complex process, phenomenon, or concept; provide an accurate summary of the text distinct from prior knowledge or opinions.
  • Engage in argument from evidence.
  • Communicate information.
Students understand that:
  • Nuclear processes, including fusion, fission, and radioactive decays of unstable nuclei, involve release or absorption of energy.
  • Half-life can be used to date the age of organic objects.
AMSTI Resources:
ASIM Chemistry Module:
Analyzing Radiation; Half-Life Simulation
Learning Objectives:

Students will be able to determine, compare, and contrast the half-lives of four radioactive elements. 

Students will utilize a virtual simulation to develop models to illustrate the concept of half-life for radioactive decay.

  Strategies, Preparations and Variations  

1. Students will follow the procedure instructions 1-10 for the virtual lab.

2. Students will record their results in a table digitally and on their own paper.

3. The student will graph the results using the online interactive.

4. Students will answer the review questions in their journal on the online interactive.

Assessment Strategies:

The teacher will assess students' completed answers to the five journal questions at the end of the lab which will require using models from the online interactive.

Advanced Preparation:

The teacher should have previously discussed atoms and radioactive decay before beginning the lesson. Students should also know the meaning of an isotope.

This virtual lab does not give the student an option to save the activity, so the teacher should instruct the students to Print Screen to save as a PDF and send to the teacher, or print and turn in the results.

The teacher could also create a worksheet for students to record their results and turn in the work.

Variation Tips (optional):

Have students create their own models to demonstrate radioactive decay. 

Notes or Recommendations (optional):

The teacher should present radioactivity and atoms before introducing the activity. This virtual simulation requires Flash and should be played using a browser that supports Flash. 

  Keywords and Search Tags  
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