Uranium-235

  • uranium-235, 235u
    heuraniumc.jpg
    uranium metal highly enriched in uranium-235
    general
    symbol235u
    namesuranium-235, u-235
    protons92
    neutrons143
    nuclide data
    natural abundance0.72%
    half-life703,800,000 years
    parent isotopes235pa
    235np
    239pu
    decay products231th
    isotope mass235.0439299 u
    spin7/2−
    excess energy40914.062 ± 1.970 kev
    binding energy1783870.285 ± 1.996 kev
    decay modes
    decay modedecay energy (mev)
    alpha4.679
    isotopes of uranium
    complete table of nuclides

    uranium-235 (235u) is an isotope of uranium making up about 0.72% of natural uranium. unlike the predominant isotope uranium-238, it is fissile, i.e., it can sustain a fission chain reaction. it is the only fissile isotope that is primordial and found in relatively significant quantities in nature.

    uranium-235 has a half-life of 703.8 million years. it was discovered in 1935 by arthur jeffrey dempster. its fission cross section for slow thermal neutrons is about 584.994 barns. for fast neutrons it is on the order of 1 barn.[1] most but not all neutron absorptions result in fission; a minority result in neutron capture forming uranium-236.

  • natural decay chain
  • fission
  • uses
  • references
  • external links

Uranium-235, 235U
HEUraniumC.jpg
Uranium metal highly enriched in uranium-235
General
Symbol235U
Namesuranium-235, U-235
Protons92
Neutrons143
Nuclide data
Natural abundance0.72%
Half-life703,800,000 years
Parent isotopes235Pa
235Np
239Pu
Decay products231Th
Isotope mass235.0439299 u
Spin7/2−
Excess energy40914.062 ± 1.970 keV
Binding energy1783870.285 ± 1.996 keV
Decay modes
Decay modeDecay energy (MeV)
Alpha4.679
Isotopes of uranium
Complete table of nuclides

Uranium-235 (235U) is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope uranium-238, it is fissile, i.e., it can sustain a fission chain reaction. It is the only fissile isotope that is primordial and found in relatively significant quantities in nature.

Uranium-235 has a half-life of 703.8 million years. It was discovered in 1935 by Arthur Jeffrey Dempster. Its fission cross section for slow thermal neutrons is about 584.994 barns. For fast neutrons it is on the order of 1 barn.[1] Most but not all neutron absorptions result in fission; a minority result in neutron capture forming uranium-236.