Fission and Fusion of Atomic Nuclei and Radiation in Your Life
Nuclear Fission Fission – the splitting of a nucleus into smaller fragments. (occurs by isotopes being bombarded with neutrons) Nuclear reactions can release enormous amounts of energy! Much more than chemical reactions. Ex. 10n + 23592U ----> 14256Ba + 9136Kr + 310n + energy Fission products from nuclear reactors are highly radioactive, remain so for a considerable period of time, and cannot simply be discarded. (Nuclear Waste) Advantages of a fission reaction are: Relatively little fuel is needed
Nuclear Fusion Fusion – occurs when the nuclei combine to produce a nucleus of greater mass. (Results from fusion: energy released by the sun) Ex. 11H + 11H ---> 21H + 0+1e Fusion reactions- small nuclei combine and when they do, they release much more energy than fission reactions. Only occur at temperatures exceeding 40 million degrees Celsius!!! This high activation energy is a huge problem in utilizing this energy as an inexpensive and readily available fuel source. One major advantage of fusion is that the products are not highly radioactive.
Risks of Radioactivity Biological exposure Long-term storage Disposal Nuclear Accidents
Beneficial Uses of Radioactive Isotopes Radioactive dating C-14 to C-12 ratio in dating living organisms U-238 to Pb-206 ratio in dating geological formations Detection and treatment of disease I-131 – used for diagnosing and treating thyroid disorder Co-60 –treats cancer Tc-99m – determines the location of brain tumors & detects the presence of cancerous cells in bone marrow Industrial chemistry and measurement Radioisotopes are used in food preservation (Radiation can kill bacteria, mold, yeast and even insect eggs.)
25.3 Section Assessment pg. 813 #’s 17 & 20 Study for Quiz Chapter 25 Study for Test Organic Chem. – Nuclear Chem.