From the list below, identify those elements that qualify as fissionable materials________________?
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Answer: A. U233andPu239
Explanation
Fissionable materials are isotopes capable of sustaining a nuclear fission chain reaction upon absorbing neutrons. Uranium-233 and plutonium-239 are primary fissile isotopes produced artificially in nuclear reactors. Both isotopes capture thermal neutrons efficiently and release massive amounts of energy through nuclear splitting. Nuclear fission splits heavy atomic nuclei into lighter elements accompanied by large energy and neutron releases. Uranium-233 is bred from thorium-232, while plutonium-239 is bred from uranium-238 inside nuclear reactors. Fissile materials serve as primary nuclear fuels for power generation and advanced reactor research.
Nuclear power plants utilize fissionable isotopes to generate carbon-free electricity for global energy grids. Reactor physicists calculate neutron cross-sections to manage fuel burnup and criticality in commercial reactors. Advanced fuel cycle research explores thorium and uranium-233 breeding for sustainable nuclear energy production. Pairings containing unstable or non-existent isotopes like uranium-231 or plutonium-233 do not represent primary fissile fuels. Isotopes like plutonium-235 are not stable fissile materials used in standard nuclear reactor fuel cycles. Uranium-238 is fertile rather than fissile, requiring fast neutrons or transmutation before sustaining fission.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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