Plantilya:Infobox neptunium

Neptunium
93Np
Pm ↑ Np ↓ (Uqp) Periodic table uranium ← neptunium → plutonium
Panagway
silvery metallic
Kinatibuk-ang mga kinaiya
Ngalan, simbolo, kaiphan	neptunium, Np, 93
Paglitok	/nɛpˈtjuːniəm/ [[Help:Pronunciation respelling key|nep-Plantilya:Smallcaps all-nee-əm]]
Kategoriyang elemento	aktinido
Group, period, block	[[group {{{group}}} element|{{{group}}}]], 7, f
Gibug-aton sa atomo	(237)
Kontorno sa elektron	[Rn] 5f4 6d1 7s2 2, 8, 18, 32, 22, 9, 2 Electron shells of neptunium (2, 8, 18, 32, 22, 9, 2)
History
Pagkadiskobre	Edwin McMillan and Philip H. Abelson (1940)
Physical properties
Phase	magahi
Density (near r.t.)	20.45 g·cm−3
Melting point	910 K, 637 °C, 1179 °F
Boiling point	4273 K, 4000 °C, 7232 °F
Heat of fusion	3.20 kJ·mol−1
Heat of vaporization	336 kJ·mol−1
Molar heat capacity	29.46 J·mol−1·K−1
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k at T (K) 2194 2437
Atomic properties
Oxidation states	7, 6, 5, 4, 3 (amphoteric oxide)
Electronegativity	1.36 (Pauling scale)
Ionization energies	1st: 604.5 kJ·mol−1
Atomic radius	155 pm
Covalent radius	190±1 pm
Miscellanea
Crystal structure	orthorhombic
Magnetic ordering	paramagnetic
Electrical resistivity	(22 °C) 1.220 µΩ·m
Thermal conductivity	6.3 W·m−1·K−1
CAS registry number	7439-99-8
Most stable isotopes
Main article: Isotopes of neptunium
iso NA half-life DM DE (MeV) DP 235Np syn 396.1 d α 5.192 231Pa ε 0.124 235U 236Np syn 1.54×105 y ε 0.940 236U β− 0.940 236Pu α 5.020 232Pa 237Np trace 2.144×106 y SF & α 4.959 233Pa 239Np trace 2.356 d β− 0.218 239Pu