1. Radioactivity and types of Radiation Contents: Discovery of Radiation Types of Decay/Radiation Whiteboard

2. Discovery of Radioactivity TOC Antoine Henri Becquerel 1852-1908 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) Parent Nucleus (Before) Daughter Nucleus (After) Radiation

3. Mass + energy Charge Number of nucleons Conservation Laws - things which are neither created nor destroyed

4. Types of decay and radiation TOC 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

6. Whiteboards: Decay Products 11 | 2 | 3 | 4 | 52345 TOC

7. W 210 82 Pb ______ +  206/80 Hg  = 2p2n, 4 nucleons, 2 protons 210 - 4 = 206 82 - 2 = 80 Hg (Mercury)

8. W  = 2p2n, 4 nucleons, 2 protons 145 - 4 = 141 61 - 2 = 59 Pr (Praseodymium) 145 61 Pm ______ +  141/59 Praseodymium

9. W 15 8 O ______ +  + 15/7 N  + = Proton turns to a neutron Nucleons remain unchanged Z = 8 - 1 = 7 (Nitrogen)

10. W 40 19 K ______ +  + 40/18 Ar  + = Proton turns to a neutron Nucleons remain unchanged Z = 19 - 1 = 18 Ar

11. W 40 19 K ______ +  - 40/20 Ca  - = Neutron turns to proton Nucleons remain unchanged Z = 19 + 1 = 20 Ca

12. W 60 27 Co ______ +  - 60/28 Ni  - = Neutron turns to proton Nucleons remain unchanged Z = 27 + 1 = 28 Ni

13. W 222 86 Rn ______ +  222/86 Rn  = High energy photon Nucleons remain unchanged Protons remain unchanged

14. Decay series: U238>Th234+  Th234>Pa234+  Pa234>U234+  U234>Th230+  Th230>Ra226+  Ra226>Rn222+  Rn222>Po218+  Uh - then it gets a little complicated Eventually the product is stable Online Nuclides