Encyclopedia > Neptunium

Article Content

Neptunium

General

Name, Symbol, Number

Neptunium, Np, 93

Chemical series

Actinides

Group, Period, Block

_ [?], 7 , f

Density, Hardness

20250 kg/m³, n/a

Appearance

silvery

Atomic Properties

Atomic weight

237.0482 amu

Atomic radius (calc.)

n/a (n/a) pm

Covalent radius

n/a pm

van der Waals radius

n/a pm

Electron configuration

[Rn]7s²5f⁴6d¹

e^- 's per energy level

Oxidation states (Oxide)

Crystal structure

3 forms: orthorhombic, tetragonal and cubic

Physical Properties

State of matter

solid (__)

Melting point

_ K (_ °F)

Boiling point

_ K (_ °F)

Molar volume

_ ×10^-3 m³/mol

Heat of vaporization

n/a kJ/mol

Heat of fusion

_ kJ/mol

Vapor pressure

unknown Pa at 1323 K

Velocity of sound

unknown m/s at 293.15 K

Miscellaneous

Electronegativity

_ (Pauling scale)

Specific heat capacity

unknown J/(kg*K)

Electrical conductivity

unknown 10⁶/m ohm

Thermal conductivity

_ W/(m*K)

1^st ionization potential

_ kJ/mol

2^nd ionization potential

_ kJ/mol

3^rd ionization potential

unknown kJ/mol

4^th ionization potential

unknown kJ/mol

Most Stable Isotopes

iso	NA	half-life	DM	DE M eV	DP
²³⁷Np	{syn.}	2.14 · 10⁶ years	_	_	_

SI units & STP are used except where noted.

Neptunium, also known less commonly as poseidonium, is a chemical element, in the periodic table that has the symbol Np and atom number 93.

External Link Los Alamos National Laboratory's Chemistry Division: Periodic Table - Neptunium

http://pearl1.lanl.gov/periodic/elements/93

See: Periodic Table

All Wikipedia text is available under the terms of the GNU Free Documentation License

Search Encyclopedia

Search over one million articles, find something about almost anything!