Periodic Table of Elements

Element Neptunium - Np

Comprehensive data on the chemical element Neptunium is provided on this page; including scores of properties, element names in many languages, most known nuclides of Neptunium. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

Neptunium Menu

Overview of Neptunium

Neptunium's Name in Other Languages

  • Latin: Neptunium
  • Czech: Neptunium
  • Croatian: Neptunij
  • French: Neptunium
  • German: Neptunium - s
  • Italian: Nettunio
  • Norwegian: Neptunium
  • Portuguese: Neptúnio
  • Russian: Нептуний
  • Spanish: Neptunio
  • Swedish: Neptunium

Atomic Structure of Neptunium

Chemical Properties of Neptunium

Physical Properties of Neptunium

Regulatory / Health

  • CAS Number
    • 7439-99-8
  • NFPA 704
    • Health:
    • Fire:
    • Reactivity:
    • Special Hazard: Radioactive<
    • OSHA Permissible Exposure Limit (PEL)
      • No limits set by OSHA
    • OSHA PEL Vacated 1989
      • No limits set by OSHA
    • NIOSH Recommended Exposure Limit (REL)
      • No limits set by NIOSH
    • Levels In Humans:
      Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
      • Blood/mg dm-3: nil
      • Bone/p.p.m: nil
      • Liver/p.p.m: nil
      • Muscle/p.p.m: nil
      • Daily Dietary Intake: nil
      • Total Mass In Avg. 70kg human: nil

    Who / Where / When / How

    • Discoverer: Edwin M. McMillan, Philip H. Abelson
    • Discovery Location: Berkeley California United States
    • Discovery Year: 1940
    • Name Origin:
      From planet Neptune.
    • Abundance of Neptunium:
      • Earth's Crust/p.p.m.: N/A
      • Seawater/p.p.m.: nil
      • Atmosphere/p.p.m.: N/A
      • Sun (Relative to H=1E12): N/A
    • Sources of Neptunium:
      Produced by bombarding uranium with slow neutrons. Neptunium is present in extremely small quantitles in Uranium ores and is created when a neutron that is emitted by one uranium atom undergoing fission is captured in the nucleus of another uranium atom. Although it is present in uranium rich ores, it is not extracted from this source.
    • Uses of Neptunium:
      Used in neutron detection instruments.
    • Additional Notes:
      Normally neptunium is never encountered outside of nuclear facilities and nuclear research facilities.

    Neptunium Menu


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