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About Nuclear Change II UNIT 7 DAY 3 What are we going to learn - - PowerPoint PPT Presentation
About Nuclear Change II UNIT 7 DAY 3 What are we going to learn - - PowerPoint PPT Presentation
Thinking Like a Chemist About Nuclear Change II UNIT 7 DAY 3 What are we going to learn today? Isotopic Stability Ionizing Radiation QUIZ: Clicker Question The following is an example of: 11 Na 22 22 10 Ne + 0 1 e a) Fission b) Fusion
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The following is an example of:
22 11Na 22 10Ne + 0 1e
a) Fission b) Fusion c) Alpha decay d) Beta decay e) positron decay
QUIZ: Clicker Question
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What is nuclear radiation?
- A. High energy electrons
- B. High energy small nuclei
- C. high energy electromagnetic radiation
- D. A & B
- E. all of the above
POLL: CLICKER QUESTION
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Three basic types of nuclear radiation
alpha radiation positive and massive beta radiation negative and low mass gamma radiation uncharged (no mass)
Radioactivity – the spontaneous emission of radiation by certain isotopes of certain elements - Madame Curie
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Where does radiation come from?
- Unstable radioisotopes
– Naturally found in environment – Made by humans for medical, energy, defense purposes
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Radioactive Decay – just happens
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WORKSHEET: Continuing activity from last class. Start with #5.
In the first equation and on the chart: Rn should have an atomic number of 86 and Po has an atomic number of 84. Mass numbers are correct.
215 86Rn 211 84Po + 4 2He
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Plot of Neutrons vs Protons
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Band of Stability
http://www-nds.iaea.org/relnsd/vcharthtml/VChartHTML.html
DISCOVER THE TYPES OF RADIATION THAT SHOULD OCCUR FOR EACH PART OF GRAPH
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Radioactive Decay – Band of Stability
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Three basic types of nuclear radiation
alpha radiation positive and massive beta radiation negative and low mass gamma radiation uncharged (no mass)
Radioactivity – the spontaneous emission of radiation by certain isotopes of certain elements - Madame Curie
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Effects Are Different
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Alpha Particles
- INSIDE BODY = HARMFUL
– bare Helium nucleus will rip electrons off molecules – ionization of biomolecules = unhealthy you
- Generally not harmful as they are absorbed by
your outer layer of dead skin
– (bad news if they get in your lungs!)
- http://www.epa.gov/rpdweb00/understand/al
pha.html#affecthealth
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Beta Decay
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Gamma Rays
- This is what will do you in.
- Hard to protect against. Highly ionizing.
- Like the world’s worst sunburn (except the
radiation can penetrate skin)
- http://www.epa.gov/rpdweb00/understand/g
amma.html#affecthealth
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RADIOACTIVITY DEMO
KCl salt: K-40, g Lantern mantle: Th-232 and daughters, a b g Monazite Rock: Th-232 and daughters, a b g Demo Button 1: Cs-137, g Demo Button 2: Ra-226, g
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A Geiger counter shows that a sample is emitting radiation. Placing a piece of paper or wood between the sample and the device does not diminish the counts, but placing a piece of lead between the sample and device stops the detection of radiation. What type of radiation is being emitted?
- A. α
- B. β
- C. γ
POLL: Clicker Question
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What did we learn today?
Isotopic Stability Depends on Neutron to Proton Ratio Decay “Particles” – Ionizing Radiation alpha beta gamma positron
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