NpZ =  93

From the Latin "Neptunus", meaning "Neptune"
(AM) Atomic Mass 237.0482  amu    Oxidation States +3, +4, +5, +6
   (BP) Boiling Point 3902  °C    (MP) Melting Point 640  °C
   (ρ) Density n/a    Crystal Structure Orthorhombic
   ( χ ) Electronegativity 1.3    (AR) Atomic Radius n/a
   Physical State Solid (C) Heat Capacity n/a
Electronic-Config [Rn]  5f4  6d1  7s2     (I1) First Ionization E 597.24  kJ/mol
   (ΔHvap) Heat of Vaporization 336  kJ/mol     (ΔHfus) Heat of Fusion 3.2  kJ/mol
   Year of Discovery 1940    Location of Discovery U. Cal, Berkley
(E°) Standard Potential Np3+⇔ Np (-1.856 V)
Stable isotopes None. All isotopes are man-made and radioactive
Discovered/Synthesized by Edwin M. McMillian, Philip H. Abelson
Natural Source Not found in nature, man-made, synthetic
Common Uses Neutron detectors, dosimeters, possibly nuclear weapons
Other Info First actinide to be synthesized
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