Radioactivity and types of Radiation

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• Radioactivity and types of Radiation
• Contents
• Discovery of Radiation
• Types of Decay/Radiation
• Whiteboard

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Discovery of Radioactivity
Studying phosphorescence of U salts Salts cloud
film on protected plates Ionized air Could be
deflected by B field (unlike X rays) Discovered
radioactive decay (demo radioactive rocks)
Antoine Henri Becquerel 1852-1908
Parent Nucleus (Before)
Daughter Nucleus (After)
Radiation
TOC
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Conservation Laws - things which are neither
created nor destroyed

• Mass energy
• Charge
• Number of nucleons

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Types of decay and radiation
Decay Type ? (Alpha) ?- (Beta-) ?
(Beta) ? (Gamma)
What it is 2p2n (He nucleus) e- (electron) e
(Positron) High energy Photon (Small ?)
Effect on Parent A - 4, Z - 2 A - 0, Z 1
(Conservation of charge) (neutron to proton) A
- 0, Z - 1 (proton to neutron) A - 0, Z -
0 Parent loses mass
TOC
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Whiteboards Decay Products 1 2 3 4 5
TOC
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21082Pb ______ ?
? 2p2n, 4 nucleons, 2 protons 210 - 4 206 82
- 2 80 Hg (Mercury)
W
206/80 Hg
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14561Pm ______ ?
? 2p2n, 4 nucleons, 2 protons 145 - 4 141 61
- 2 59 Pr (Praseodymium)
W
141/59 Praseodymium
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158O ______ ?
? Proton turns to a neutron Nucleons remain
unchanged Z 8 - 1 7 (Nitrogen)
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15/7 N
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4019K ______ ?
? Proton turns to a neutron Nucleons remain
unchanged Z 19 - 1 18 Ar
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40/18 Ar
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4019K ______ ?-
?- Neutron turns to proton Nucleons remain
unchanged Z 19 1 20 Ca
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40/20 Ca
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6027Co ______ ?-
?- Neutron turns to proton Nucleons remain
unchanged Z 27 1 28 Ni
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60/28 Ni
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22286Rn ______ ?
? High energy photon Nucleons remain
unchanged Protons remain unchanged
W
222/86 Rn
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• Decay series
• U238gtTh234?
• Th234gtPa234?
• Pa234gtU234?
• U234gtTh230?
• Th230gtRa226?
• Ra226gtRn222?
• Rn222gtPo218?
• Uh - then it gets a little complicated
• Eventually the product is stable
• Online Nuclides