Template:Infobox neptunium

Neptunium, ₉₃Np

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Neptunium
Pronunciation	/nɛpˈtjuːniəm/ ​(nep-TEW-nee-əm)
Appearance	silvery metallic
Mass number	[237]
Neptunium in the periodic table
Hydrogen Helium Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson Pm ↑ Np ↓ — uranium ← neptunium → plutonium
Atomic number (Z)	93
Group	f-block groups (no number)
Period	period 7
Block	f-block
Electron configuration	[Rn] 5f4 6d1 7s2
Electrons per shell	2, 8, 18, 32, 22, 9, 2
Physical properties
Phase at STP	solid
Melting point	912±3 K ​(639±3 °C, ​1182±5 °F)
Boiling point	4447 K ​(4174 °C, ​7545 °F) (extrapolated)
Density (at 20° C)	20.48 g/cm3 (237Np)
Heat of fusion	5.19 kJ/mol
Heat of vaporization	336 kJ/mol
Molar heat capacity	29.46 J/(mol·K)
Vapor pressure P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 2194 2437
Atomic properties
Oxidation states	common: +5 +2,? +3, +4, +6, +7
Electronegativity	Pauling scale: 1.36
Ionization energies	1st: 604.5 kJ/mol
Atomic radius	empirical: 155 pm
Covalent radius	190±1 pm
Color lines in a spectral range Spectral lines of neptunium
Other properties
Natural occurrence	from decay
Crystal structure	​orthorhombic (oP8)
Lattice constants	Orthorhombic crystal structure for neptunium a = 472.3 pm b = 488.7 pm c = 666.3 pm (at 20 °C)
Thermal conductivity	6.3 W/(m⋅K)
Electrical resistivity	1.220 µΩ⋅m (at 22 °C)
Magnetic ordering	paramagnetic
CAS Number	7439-99-8
History
Naming	after planet Neptune, itself named after Roman god of the sea Neptune
Discovery	Edwin McMillan and Philip H. Abelson (1940)
Isotopes of neptunium
Main isotopes Decay abun­dance half-life (t1/2) mode pro­duct 235Np synth 396.1 d α 231Pa ε 235U 236Np synth 1.54×105 y ε 236U β− 236Pu α 232Pa 237Np trace 2.144×106 y α 233Pa 239Np trace 2.356 d β− 239Pu

Np · Neptunium
U ← ibox U	iso 93 Np  [] IB-Np [] IBisos []	→ Pu ibox Pu
File:Symbol category class.svg cat:Np (0) File:Symbol category class.svg cat:Np-isotopes (0) File:Commons-logo.svg Commons File:Wikidata-logo.svg Wikidata:Q1105 File:Wiktionary-logo.svg Wiktionary
indexes by PT (page)

child table, as reused in {IB-Np}
Main isotopes of neptunium
Main isotopes Decay abun­dance half-life (t1/2) mode pro­duct 235Np synth 396.1 d α 231Pa ε 235U 236Np synth 1.54×105 y ε 236U β− 236Pu α 232Pa 237Np trace 2.144×106 y α 233Pa 239Np trace 2.356 d β− 239Pu

Data sets read by {{Infobox element}}
Name and identifiers
Symbol etymology (11 non-trivial)
Top image (caption, alt)	caption: alt:
Pronunciation
Allotropes (overview)
Group (overview)
Period (overview)
Block (overview)
Natural occurrence
Phase at STP
Oxidation states
Spectral lines image
Electron configuration (cmt, ref)
Isotopes
Standard atomic weight
most stable isotope
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Wikidata *
* Not used in {{Infobox element}} (2023-01-01) See also {{Index of data sets}} · Cat:data sets (0) · (this table: )

References

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