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Teaching the Concept of Half-Life . Lesson Sequence. Lesson 1: Radioactive Decay Bohr-Rutherford model of atom, isotopes – review Alpha, Beta and Gamma Decay Lesson 2: Measuring the rate of Radioactive Decay Process Half-Life Aplication of Half-Life: Carbon Dating - PowerPoint PPT Presentation
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Teaching the Concept of Half-Life
Lesson 1: Radioactive Decay Bohr-Rutherford model of atom, isotopes – review Alpha, Beta and Gamma Decay
Lesson 2: Measuring the rate of Radioactive Decay Process Half-Life Aplication of Half-Life: Carbon Dating
Lesson 3: Nuclear Fission and Nuclear Power Generation Mass Energy Equivalence Nuclear Fuel Chain Reactions
Lesson 4: Nuclear Fusion Nuclear Stability Stellar Fusion Magnetic Confinement Fusion
Lesson 5: Applications of Nuclear Technology Candu Reactors, Waste disposal Medical applications of Radioisotopes
Lesson 6: Nuclear Energy : Benefits and Hazards
Lesson Sequence
Overall:
D3. demonstrate an understanding of work, efficiency, power, gravitational potential energy, kinetic energy, nuclear energy, and thermal energy and its transfer (heat).
Specific:
D1.2 assess, on the basis of research, how technologies related to nuclear, thermal, or geothermal energy affect society and the environment (e.g., thermal regulating units, radiopharmaceuticals, dry-steam power plants, ground-source heat pumps) [IP, PR, AI, C]
D2.1 use appropriate terminology related to energy transformations, including, but not limited to: mechanical energy, gravitational potential energy, kinetic energy, work, power, fission, fusion, heat, heat capacity, temperature, and latent heat [C]
D2.7 compare and contrast the input energy, useful output energy, and per cent efficiency of selected energy generation methods (e.g., hydroelectric, thermal, geothermal, nuclear fission, nuclear fusion, wind, solar) [AI, C]
D2.8 investigate the relationship between the concepts of conservation of mass and conservation of energy, and solve problems using the mass– energy equivalence [PR, AI]
D3.6 describe and compare nuclear fission and nuclear fusion
D3.9 identify and describe the structure of common nuclear isotopes (e.g., hydrogen, deuterium, tritium)
D3.10 compare the characteristics of (e.g., mass, charge, speed, penetrating power, ionizing ability) and safety precautions related to alpha particles, beta particles, and gamma rays
D3.12 explain the energy transformations that occur within a nuclear power plant, with reference to the laws of thermodynamics (e.g. nuclear fission results in the liberation of energy, which is converted into thermal energy; the thermal energy is converted into electrical energy and waste heat, using a steam turbine)
Curriculum Expectations for Energy and Society Unit
After the earthquake and tsunami hit Japan and its nuclear plants in 2011, the world held its breath
These headlines were almost in all newspapers and television stations
Do you know how to measure the rate of radioactive decay of radiocative elements?
My guess is you do not.
Let us learn today how to do it!
• What is the risk from Caesium-137 and Iodine -131 at Fukushima? • How long does it take for radioactive atoms to decay?
Introduction to Half-Life
• D3.11 explain radioactive half-life for a given radioisotope, and describe its applications and their consequences
Specific Curriculum expectations for the lesson:
• Virtual Lab: Measuring the Rate of Radioactive Decay http://glencoe.mcgraw-hill.com/sites/dl/free/0078693896/280405/E18.html
Students will use an inquiry based approach to investigate the meaning of radioactive half-life
Students interactively learn that radioactive materials decay at different rates
Half- Life: Teaching Strategy 1: Inquiry Based Learning:
The average length of time it takes a radioactive material to decay to half of its original mass
What is Half–Life?
The half-life of any given isotope is actually an average time for a particular parent atom to decay to its daughter atom
The larger the sample size, the more accurately a material decays according to its half-life
Half-Life Equation:
A - massA0 - initial sample masst - timeh – half-life
What is Half–Life?
• While standing, each of students will be flipping a
penny
• Each time they flip, one half-life will have passed
• If a penny lands on heads, the student is regarded as radioactive, has decayed and needs to sit
• If a penny lands on tails, the student have not decayed (remain standing)
• After each half-life , a teacher should count students who stand and plot data on a the overhead
• Students will be asked to predict what will happen to the numbers of remaining parent isotopes
Students will participate in a demonstration that visually illustrates the concept of half-life
Half- Life: Teaching Strategy 2: Demonstration
Students will learn what carbon dating is and why Carbon -14 is a useful isotope for dating fossils and
other archeological objects Carbon 14 Decay: http://www.youtube.com/watch?v=81dWTeregEA
Carbon Dating: http://www.youtube.com/watch?v=31P9pcPStg&feature=related
Short Dicussion: Student will share what they understood from these videos
Half-Life: Teaching Strategy 3: Application of Half-Life: Introduction to Carbon Dating –Videos and Discussion
• Students will find out the age of five different „fossils” a bag represents a fossil and beads inside the bag
–> atoms
• Students need to : use half-life properties of isotopes to determine the
age of different fossils
count the number of parent and daughter isotope atoms in each bag
determine how many half-lives the isotope has gone through
determine the age of the fossil
This hands-on activity allows students to gain a better understanding of how scientists use isotopes to determine the age of fossils and
archeological objects
Half-Life Teaching Strategy 4: Radiometric dating activity – What is the
age of the fossil?
Potential Student Difficulty Solution
Show your students a demonstration with popping popcorn
Explain that when popcorn kernels are poured into popcorn popper, it is impossible to predict which kernel pops first
When they are removed from the
popper they are not kernels any more. They have been transformed and changed forever
Understanding that radioactive decay is a
spontaneous process that involves irreversible
transformation of one element into another
Potential Student Difficulty
Realizing the difference between radioactivity and radioactive decay
Solution
Radioactivity
refers to the particles which are emitted from nuclei as a result of nuclear instability
Radioactive decay
the process by which a radioactive atom’s nucleus breaks apart and forms different atoms
Show your student the following poster and explain using pictures what the difference is
Potential Student Difficulty Solution
Understanding that nuclei do not disappear when they decay
Show students an animationhttp://www.youtube.com/watch?v=o-9yt7OAYmE
Potential Student Difficulty Solution
Wrongly interpreting half-
life as half the time for the
radioactivity to disappear
Use demonstrations such as a coin toss or M&M’s to help students understand the concept
Depict the results of these demonstrations as a curve of an exponential decay function
Analyze with student the shape and changes in number of isotopes
Major safety concern should be an appropriate Internet conduct as the virtual lab is done on-line
Enough space in the classroom should be provided for students when they do their radiometric dating activity
The classroom should be free from clutter when students circulate between stations while doing radiometric dating activity
Safety Considerations
Practical Applications of Radioactive Decay
• MEDICINEdiagnostic medical imaging to detect tumors, bone fracture
(medical and dental X-ray images, SPECT, PET, MRI)
radionuclide therapy (RNT – bombarding dividing harmful cell with radiation)• EARTH SCIENCES – using C-14 for dating of geological
specimens • NUCLEAR PHYSICS – nuclear energy production
Differentiated Assesment
Assssment will be ongoing
Multiple intelligences will be taken into account while assessing students
Students will be assessed based on:
Written laboratory reports (formative and summative) Classroom discussions / small group discussions Oral responses and presentations Tests/ quizzes Problem solving assignments (numerical and non-numerical) Research assignments on applications of nucelar technology - students will be
given a chance to choose a topic and a method they would like to prepare the concept: poster, newspaper article, song, Power Point Presentation, drama, podcast, game, photo journal, demonstration, jigsaw, oral presentation
Exit tickets will be taken to check students’ understanding of delivered material
Keeping in mind a lesson on Half-Life- assessment will be based on: written lab report (formative) and classroom discussion
Students with IEP• Activities, assignments, laboratory practice, tests, quizzes
will be modified and designed to meet specific learning needs
ELL students• Will be given more time to finish their assignments• Will be provided with teacher assistance whenever possible• Will be given a chance to seat beside someone who speaks
their first language/ who speaks English but is eager to provide support
• Students will receive (in advance) a lesson outline with important words essential to do a classroom activity, lab reports
Accomodations for students with special needs
• Virtual Lab on radioactive decay (alpha decay)• http://phet.colorado.edu/en/simulation/alpha-decay
• Radioactive Dating: Looking at Half-Lives Using M&Ms• http://serc.carleton.edu/sp/mnstep/activities/34884.html
• Using Popcorn to Simulate Radioactive Decay• http://serc.carleton.edu/quantskills/activities/popcorn.html
• Activities for teaching fundamental concepts of nuclear energy and related topics (a variety of activities)• http://www.uraweb.org/reports/skoog.pdf
• Radioactive Dating Game:• http://phet.colorado.edu/en/simulation/radioactive-dating-game
• Nuclear Fission Simulation:• http://phet.colorado.edu/en/simulation/nuclear-fission
• Class as an Artifact: A Radioisotope Dating Activity:• http://www.acad.carleton.edu/curricular/BIOL/classes/bio302/pages/ClassFossil.ht
ml
Suggestions for other student labs/activities related to nucelar reactions
Students misconceptions: http://www.furryelephant.com/content/radioactivity/teaching-learning/radioactivity-misconceptions/http://serc.carleton.edu/quantskills/methods/quantlit/RadDecay.html
Demonstration of radioactive decay using pennieshttp://serc.carleton.edu/quantskills/activities/PennyDecay.html
Radiometric Dating Activityhttp://www.acad.carleton.edu/curricular/BIOL/classes/bio302/pages/half-life.html
Information about half-life - half-lives for various radioisotopes:http://theenergylibrary.com/node/11798
Physics 11 - textbook – definition and explanation of half-life, definition of radioactive decay
DiGiuseppe M., Howes Ch. , Speijer J., Stewart Ch., Bemmel H. , Vucic R., Wraight V. Physics 11. Nelson Thompson Learning
Ontario Science Curriculum Grades 11-12http://www.edu.gov.on.ca/eng/curriculum/secondary/2009science11_12.pdf
Resources
Virtual Lab: Measuring the Rate of Radioactive Decay http://glencoe.mcgraw-hill.com/sites/dl/free/0078693896/280405/E18.html
Worksheet on Half- Lifehttp://mysite.cherokee.k12.ga.us/personal/brenda_priest/site/Subject%202%20Notes/1/Virtual%20Half%20Life%20Lab.pdf
Radioactive Decay – picture:http://eqseis.geosc.psu.edu/~cammon/HTML/Classes/IntroQuakes/Notes/earth_origin_lecture.html
Radioactivity -definition and picture:http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact.html
Half-Life – picture on the main site:http://hendrix2.uoregon.edu/~imamura/121/lecture-9/lecture-9.html
Explaining Radioactivityhttp://www.youtube.com/watch?v=o-9yt7OAYmE
Resources
Carbon Dating:http://www.youtube.com/watch?v=31P9pcPStg&feature=related
Carbon 14 Decayhttp://www.youtube.com/watch?v=81dWTeregEA
Using Popcorn to Simulate Radioactive Decayhttp://serc.carleton.edu/quantskills/activities/popcorn.html
Half-Life Graph:http://web.princeton.edu/sites/ehs/osradtraining/radiationproperties/radiationproperties.htm
Resources