uranium-235: Quick Facts

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Photos

A diagram illustrating nuclear fission: a neutron strikes a uranium-235 nucleus, splitting it into barium and krypton nuclei, releasing energy and additional neutrons.

Diagram illustrating the moderated, controlled fission of uranium-235, showing uranium nuclei splitting after absorbing slow neutrons, releasing fast neutrons, and how moderators slow neutrons to sustain a controlled chain reaction.

A flowchart diagram of the nuclear fuel cycle shows the process from uranium mining and extraction, through enrichment, fuel fabrication, reactor use, spent fuel reprocessing, and waste disposal, with arrows tracing material movement and recycling steps.

decay of uranium-235

mass distribution dependence on the energy excitation in the fission of uranium-235

Diagram of a thermonuclear warhead cut open to reveal internal components, including a primary fission trigger with deuterium-tritium gas, plutonium-239, beryllium, and chemical explosives, and a secondary fusion device with uranium-235, lithium deuteride fusion fuel, and a uranium case, all labeled for educational reference.

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Topics

depleted uranium nuclear reactor isotope uranium radioactive isotope fissile material transuranium element carbon-14 tritium cobalt-60 How Radioactive Isotopes are Used in Medicine deuterium isotopic tracer protium uranium series

Key People

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Harold C. Urey

American chemist

Abelson, Philip Hauge

Philip Hauge Abelson

American scientist

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John R. Dunning

American physicist

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Arthur Jeffrey Dempster

American physicist