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Name: Chad
Status: student
Age: 18
Location: N/A
Country: N/A
Date: 1999 

What nuclear elements are used in fission?

Elements much heavier than iron produce energy when split apart.

Elements much lighter than iron produce energy when fused together.

Tim Mooney

Basically, any heavy nucleus (I'm not exactly sure where the cutoff is - certainly, any nucleus heavier than lead) can release energy upon fission. There are only three nuclei, however, that can be used to generate nuclear power in conventional nuclear reactors, or to make nuclear weapons. These are the fissile nuclei, those that undergo fission upon absorption of thermal (slow) neutrons. These nuclei are uranium-233, uranium-235, and plutonium-239.

Richard E. Barrans Jr., Ph.D.

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