General: |
Name: Neptunium
|
Symbol: Np
|
Group: Rare Earth, Actinides
|
Atomic weight: 237.0482
|
Density @ 293 K: 20.45 g/cm3
|
Atomic volume: 11.62 cm3/mol
|
Group: Rare Earth, Actinides
|
discovered: 1940
|
|
States: |
state (s, l, g): s
|
melting point: 913.2 K
|
boiling point: 4175 K
|
Heat of fusion: 5.190 kJ/mol
|
Heat of vaporization: ?
|
|
Energies: |
1st ionization energy: 597 kJ/mole
|
electronegativity: 1.3
|
2nd ionization energy: kJ/mole
|
electron affinity: kJ/mole
|
3rd ionization energy: kJ/mole
|
Specific heat: 0.12 J/gK
|
heat atomization: kJ/mole atoms
|
|
Oxidation & Electrons: |
Shells: 2,8,18,32,23,8,2
|
electron configuration: [Rn] 5f4 6d1 7s2
|
minimum oxidation number: 0
|
maximum oxidation number: 7
|
min. common oxidation no.: 0
|
max. common oxidation no.: 5
|
|
Appearance & Characteristics: |
structure: special:complex
|
color: silvery
|
uses:
|
toxicity:
|
hardness: mohs
|
characteristics: Radioactive
|
|
Reactions: |
reaction with air:
|
reaction with 6M HCl:
|
reaction with 6M HCl:
|
reaction with 15M HNO3:
|
reaction with 6M NaOH:
|
|
Other Forms: |
number of isotopes: 0
|
hydride(s): NpH2 NpH3
|
oxide(s): NpO NpO2 Np2O5
|
chloride(s): NpCl3 NpCl4
|
|
Radius: |
ionic radius (2- ion): pm
|
ionic radius (1- ion): pm
|
atomic radius: 155 pm
|
ionic radius (1+ ion): pm
|
ionic radius (2+ ion): 124 pm
|
ionic radius (3+ ion): 115 pm
|
|
Conductivity: |
thermal conductivity: 6.3 J/m-sec-deg
|
electrical conductivity: 1/mohm-cm
|
polarizability: 24.8 A^3
|
|
Abundance: |
source: Synthetic
|
rel. abund. solar system: log
|
abundance earth's crust: log
|
cost, pure: $/100g
|
cost, bulk: $/100g
|
|