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http://www.youtube.com/watch?v=Pz6eHI_XM5k. NUCLEAR CHEMISTRY. reaction. 11/04 RADIOACTIVITY. Marie Curie was a Polish scientist whose research led to many discoveries about radiation and radioactive elements. In 1903 she won the Nobel Prize for Physics

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  1. http://www.youtube.com/watch?v=Pz6eHI_XM5k NUCLEAR CHEMISTRY

  2. reaction

  3. 11/04 RADIOACTIVITY Marie Curie was a Polish scientist whose research led to many discoveries about radiation and radioactive elements. In 1903 she won the Nobel Prize for Physics (shared w/husband Pierre). She won the Prize again in 1911 for Chemistry. In 1934 she died from leukemia, caused by her long-term exposure to radioactivity.

  4. Key Terms: radioactivity: radiation: radio-isotopes:

  5. Need to Remember: mass # (p+ + no) element symbol atomic # ( #p+)

  6. Notation for sub-atomic particles mass # charge # n (p+) p (p+) ep+

  7. Chemical rxn vs Nuclear reaction:

  8. Uranium-238 is used in nuclear reactors to generate electricity. The process involves uranium-238 changing to lead-209 238 209 U Pb 92 82 rxn is spontaneous in nature, the UNSTABLE uranium will decay until it becomes a stable isotope, lead but it can speeded up by hitting the U nuclei with neutrons

  9. NUCLEAR REACTIONS: A change in the nucleus - an element changes into a different element When the nucleus of an atom is unstable, it will DECAY and emit particles. This is called RADIOACTIVE DECAY , the particles given off are RADIATION

  10. Half-life: Every radioactive isotope has a half-life. This is the amount of time required for one-half the radioactive nuclei to decay into a stable element Isotope half-life radiation carbon-14 5730 years beta potassium-40 1.25 x 109 yrs beta, gamma radium-226 1.6 x 103 yrs alpha, gamma radon-222 3.8 days alpha polonium-210 138 days alpha uranium-238 4.5 billion yrs all 3

  11. Carbon dating: C-14 has a half-life of 5730 years and is used to date artifacts made of carbon – HUMAN bones, documents, plants All living organisms have C-14 and C-12 in a fixed ratio. After death, the ratio changes as C-14 decays to N-14. So, by comparing C-14 to C-12 the approximate age of the item can be determined between 200 and 50,000 yrs

  12. Ex: an archaeologist digs up a skull that has 1/64 of the normal amount of carbon 14 that should be present. Approximately how old is the bone? 1/2 1/4 1/8 How many half lives have occurred? 1/16 1/32 6 half lives x 5730 yr = 34,380 yrs half life 1/64

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