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2 http://www.lanl.gov/science/1663/images/reactor.jpg

3  Nuclear Bomb of 1945 known as “ fat man ” http://www.travisairmuseum.org/assets/images/fatman.jpg

4 http://library.thinkquest.org/06aug/01200/Graphics/705px-Nuclear_fireball.jpg

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6  Depends on the neutron to proton ratio  Protons & neutrons are held together by the  Band of Stability

7  Isotopes of certain unstable elements that emit particles and energy from the nucleus.  Nuclei with atomic number > 83 are radioactive  in 1896 accidentally observed radioactivity of uranium salts that were fogging photographic film.  His associates were Marie and Pierre Curie.

8  Lived in France  1898: discovered the elements and. http://www.radiochemistry.org/nuclearmedicine/pioneers/images/mariecurie.jpg

9  Winner of 1903 Nobel Prize for Physics with Henri Becquerel and her husband, Pierre Curie  Winner of the sole 1911 for Chemistry.

10      

11 Emission of  :  helium nuclei  two and two  charge +2e  can travel a few inches through air  can be stopped by a or.

12 Uranium Thorium

13 http://education.jlab.org/glossary/alphadecay.gif

14  Beta particles  : ejected from the nucleus when neutrons decay n -> p + +  -  Beta particles have the same charge and mass as "normal" electrons.  Can be stopped by or a.

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16 Thorium Protactinium

17  Gamma radiation  energy that is released.  Gamma rays are electromagnetic.  They have no mass.  Gamma radiation has no charge.  Most Penetrating, can be stopped by 1m thick or a several cm thick.

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19  They will undergo  The type of decay depends on the reason for the instability

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21  Radioactive dating  Radioactive dating – scientists can determine the approximate of an object based on the of certain radioactive nuclides present.

22 Radioactive tracers Radioactive tracers are radioactive atoms that are incorporated into substances so that of the substances can be followed by radiation detectors. – Radioactive tracers can be used by doctors to. – Radioactive tracers are also used in agriculture to determine the effectiveness of fertilizers.

23  Irradiated Food  Irradiated Food – nuclear radiation is used to of food.

24  Nuclear Power Plants  Nuclear Power Plants – use energy as heat from nuclear reactors to. They have five main components: 1.Shielding – radiation-absorbing material used to decrease exposure to radiation from nuclear reactors. 2. Fuel – usually Uranium-235. 3.Coolant – usually water, it absorbs excess heat energy. 4.Control rods – neutron-absorbing rods that limit the number of free neutrons 5.Moderator – used to slow down the fast neutrons produced by fission.

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26  Rem  Rem – The unit used to measure the biological effects of in humans.


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