| Themes > Science > Chemistry > Nuclear Chemistry > Nuclear Reactions > Transmutation > Transmutation |
Transmutation is the changing of one isotope into another. Radioactive decay is only one cause of transmutation. Another way to cause transmutation is to bombard nuclei with high energy particles, which can be done with alpha particles from natural emitters, neutrons from atomic reactors, or protons made by stripping electrons from hydrogen. To make them better, protons and alpha particles can be accelerated in an electric field, giving them greater energy to bury themselves in the target's nucleus. When a particle and a nucleus collide, the product, called a compound nucleus, is formed. The compound nucleus has a lot of energy in it, and often will eject a neutron, proton, or an electron, as well as gamma radiation, to get rid of the excess energy. For example: 42He + 147N ==> 189F ==> 178O + 11p alpha particle + nitrogen ==> flourine-18 (compound nucleus) ==> oxygen-17 + proton 11p + 73Li ==> 84Be ==> 242He proton + lithium ==> beryllium-8 ==> 2 alpha particles Radionuclides Above Atomic Number 83Through bombardment, over a thousand isotopes have been made, most of which do not occur naturally. The naturally occurring isotopes above atomic number 83 all have very long half-lives. All the elements from neptunium (atomic number 93) and up, the transuranium elements, are synthetic. Elements up to 109 have been made. To make these heavier elements, bombardment of heavier nuclei are used. For example, there have been attempts to bombard argon-40 and uranium-236 to create element 110. Some interest has been focused on making element 126, one with a magic number. |
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