Neptunium

Radioactive element
Latin nameNeptunium
english nameNeptunium
chemical symbolNp
atomic number93
relative atomic mass(237,0482)
period7
groupIII.B
classificationactinides
discovery year1940
discovererMcMillan, Abelson
melting point [°C]640
boiling point [°C]3902
density [g cm-3]20,45
electronegativity [Pauling]1,36
oxidation statesII ˜ VII
electron configuration[Rn]5f4 6d1 7s2
specific heat [J g-1K-1]0,12
heat of fusion [kJ mol-1]5,19
thermal conductivity [W m-1 K-1]6
el. conductivity [S m-1]8,3.105
1. ionizing potential [eV]6,2657
state at normal conditionssolid