1. Radioactive Particles Chart Alpha, Beta Decay Practice
Nuclear PBL Unit Day 2
Radioactive Particles Chart
Alpha, Beta Decay Practice

2. Common Core Connection
Objectives:
Today I will be able to:
Differentiate between the composition and materials required to shield alpha, beta, gamma, positron and electron capture emissions
Correctly solve and balance radioactive equations
Informal assessment – monitor student interactions as they complete the radioactive particles chart
Formal assessment – analyzing responses to the radioactive particles chart and the alpha and beta decay practice
Common Core Connection
Build Strong Content Knowledge
Value Evidence
Construct viable arguments and critique the reasoning of others

3. Lesson Sequence Evaluate: Warm – Up
Explore/Explain: Radioactive Particles Chart
Explain: Alpha and Beta Decay Notes
Elaborate: Alpha and Beta Decay Practice
Evaluate: Exit Ticket

4. Warm – Up Where is the nuclear reactor in Maryland?
How many nuclear reactors are in the United States?
Which region of the United States has the highest concentration of nuclear reactors
Note: When discussing this warm-up, reference a copy of a United States map that shows the location of nuclear re actors.

5. Maryland Nuclear Power Plant
Calvert Cliffs is Maryland’s nuclear power plant

6. Nuclear Power Plants
map: Nuclear Energy Institute

7. Objective Today I will be able to:
Differentiate between the composition and materials required to shield alpha, beta, gamma, positron and electron capture emissions
Correctly solve and balance radioactive equations

8. Homework Finish Alpha and Beta Decay Practice
Answer these questions about your radioactive incident
•What is the isotope for your radioactive incident?
•Which type of nuclear decay is your isotope undergoing?
•Write the decay equation for your isotope.
Study for Atomic Structure, Mole and History of Atom Quiz on Thursday, October 9
STEM Fair Data Collection and Analysis Due Friday, October 10

9. Agenda Warm – Up Radioactive Particles Chart
Alpha and Beta Decay Notes
Alpha and Beta Decay Practice
Exit Ticket

10. Radioactive Particles Chart

11. Add the following to the back of the radioactive particles chart
Type of Particle
How far does it travel/ What can it travel through?
How can this type of radiation be blocked?
Practical uses for the type of radiation
Alpha
Beta
Gamma

12. Radioactivity Review Notes

13. Radioactive Decay Chains
A nucleus goes through a series of decays and states before it reaches a stable configuration
Each step in the chain will have its own unique characteristics of half-life and own type of radiation emitted
Understanding helps make nuclear reactors (power) and weapons!

14. Uranium Chain Reaction

15. Types of radiation
Transformation - Results in formation of a nucleus of a new element
Alpha
Beta
Positron
Results in release of energy – not transformation
Gamma

16. Radioactive Decay – Alpha Decay
Stream of high energy alpha particles
Consists of 2 protons and 2 neutrons (identical to a positively charged particle of a Helium nuclei)
An alpha particle is composed of two protons and two neutrons, so it can be represented by a Helium-4 atom

17. Radioactive Decay – Alpha Decay
When an alpha particle breaks away from the nucleus of a radioactive atom, it has no electrons, so it carries a +2 charge
An alpha particle is typically shown with no charge, because it very rapidly picks up two electrons and becomes a neutral helium atom, instead of an ion α 4 He 4 2 2

18. Radioactive Decay – Alpha Decay
Heavy elements, such as Uranium and Thorium tend to undergo alpha decay
Alpha decay relieves the nucleus of two protons and two neutrons or a mass of 4 amu

19. Radioactive Decay – Alpha Decay
Easily stopped by clothes or paper
Only travel several cm through air
Usually does not pose a health risk unless the source of radiation enters the body

20. Radioactive Decay – Beta Decay
Consists of a stream of high speed electrons
A neutron breaks down into one p+ and one e-
The p+ stays in nucleus and e- leaves at high speed
Is able to pass through clothing and damage skin

21. Radioactive Decay – Beta Decay
Example – Iodine-131, which is used in the detection and treatment of thyroid cancer
Notice the mass number (131) remains the same, but the atomic number increases by one (53  54)
This is the result of a neutron turning into a proton and an electron – the electron leaves (as beta radiation) and the proton remains in the nucleus

22. Uranium Chain Reaction

23. Radioactive Decay – Gamma Radiation
Is a form of light (energy) that our eyes don’t see
Similar to X-rays – high energy, short wavelength radiation
No mass change associated with gamma radiation

24. Radioactive Decay – Gamma Radiation
Does not consist of particles
Usually accompanies alpha and beta radiation
Isotopes, such as Cobalt-60 release gamma radiation
Very penetrating – only stopped by lead or concrete

25. Radioactive Decay – Positron Emission
Electron with a positive charge
Formed when a proton in the nucleus decays into a neutron and a positively charged electron – emitted by the nucleus
Rarely occurs with naturally occurring isotopes – have to be man-made

26. Radioactive Decay – Electron Capture
Occurs when there are too many protons and not enough energy to release a positron
An electron from an atom’s inner shell is taken in by the nucleus, turning a proton into a neutron
Energy is released – X-Ray

27. Radioactive Decay – Practical Uses
PET scans
Smoke detectors
Nuclear weapons (WWII)
Source of electricity
Food preservation
Cancer treatment

28. Radioactive Decay – Practical Uses
Radioactive Dating
- Uses the isotope, Carbon-14
- Produced in the atmosphere by cosmic radiation
- A very small amount of CO2 contains C-14, which is taken in by plants during photosynthesis
- Animals eat plants, therefore C- 14 is part of all living things

29. Radioactive Decay – Practical Uses
Radioactive Dating (continued)
- Once an organism dies, the amount of C-14 begins to decrease and the half-life (5,730 years) can be used to determine the age
- For non-living substance, other isotopes, such as potassium-40 are used

30. Exposure to Radiation

31. Exposure to Radiation

32. Alpha and Beta Decay Practice

33. Exit Ticket Write the radioactive decay equation for:
The alpha decay of Uranium-238
The beta decay of Lead- 213