Neptunium

93
Np
Gruppe
n/a
Periode
7
Blok
f
Protons
Electrons
Neutrons
93
93
144
General Properties
Atomnummer
93
Atommasse
[237]
Mass Number
237
Kategori
Actinider
Farve
Silver
Radioactive
Ja
Named after the planet Neptune
Krystalstruktur
Simpel Orthohombisk
History
Neptunium was the first synthetic transuranium element of the actinide series to be discovered.

Neptunium was first produced by Edwin McMillan and Philip H. Abelson in 1940 at Berkeley Radiation Laboratory of the University of California.

The team produced the neptunium isotope 239Np by bombarding uranium with slow moving neutrons.
Elektroner i hver skal
2, 8, 18, 32, 22, 9, 2
Elektronkonfiguration
[Rn] 5f4 6d1 7s2
Np
Neptunium is obtained as a by-product from nuclear reactors
Physical Properties
Tilstandsform
Fast stof
Massefylde
20,45 g/cm3
Smeltepunkt
910,15 K | 637 °C | 1178,6 °F
Kogepunkt
4273,15 K | 4000 °C | 7232 °F
Smeltevarme
10 kJ/mol
Fordampningsvarme
335 kJ/mol
Varmefylde
-
Abundance in Earth's crust
n/a
Abundance in Universe
n/a
Edwin
Billede akkrediteringer: scienceworld.ro
Edwin McMillan, one of the discoverer of the element
CAS Number
7439-99-8
PubChem CID Number
n/a
Atomic Properties
Atomradius
155 pm
Kovalent radius
190 pm
Elektronegativitet
1,36 (Paulings skala)
Ionization Potential
6,2657 eV
Atomic Volume
11,62 cm3/mol
Varmeledningsevne
0,063 W/cm·K
Oxidationstrin
3, 4, 5, 6, 7
Applications
Neptunium is used mainly for research purposes.

When bombarded with neutrons 237Np is used to produce 238Pu which is used for spacecraft generators and terrestrial navigation beacons.

237Np is used in devices for detecting high-energy neutrons.
Neptunium is harmful due to its radioactivity
Isotoper
Stable Isotopes
-
Unstable Isotopes
225Np, 226Np, 227Np, 228Np, 229Np, 230Np, 231Np, 232Np, 233Np, 234Np, 235Np, 236Np, 237Np, 238Np, 239Np, 240Np, 241Np, 242Np, 243Np, 244Np