To form a 23U nucleus, you need to combine 23 protons and 23 neutrons. This can be done through a process called nuclear fission, in which a large nucleus is split into smaller nuclei, releasing energy in the process.
As for the arguments for and against reprocessing nuclear waste, proponents of reprocessing argue that it reduces the amount of waste that needs to be stored and disposed of, and allows for the reuse of valuable materials such as uranium and plutonium. Critics, however, point out that reprocessing can release harmful radioactive materials into the environment, and that the recovered materials can be used to make nuclear weapons.
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