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Nuclear & Radiochemistry

Nuclear Fission

The splitting of a heavy nucleus into two lighter nuclei with the release of neutrons and a large amount of energy.

Formula / equation ²³⁵U + n → fragments + 2–3n + energy
Unit MeV

In depth

Fission releases about 200 MeV per event, roughly fifty million times a typical combustion reaction per atom. The two fragments are usually of unequal mass and are highly radioactive, which is the origin of the long-lived waste problem.

Examples in the real world

Uranium-235 splitting into barium-141 and krypton-92 with three neutrons released.