Plutonium (Pu)

From Wikipedia, the free encyclopediaPlutonium is a transuranic radioactive chemical element with symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states.

Plutonium in the periodic table

Atomic number94
Element categoryActinide

Physical properties

Phase at STPSolid
Density19.816 g/cm3
Atomic weight244 u
Melting point912.5 K
639.35 °C
1182.83 °F
Boiling point3505 K
3231.85 °C
5849.33 °F

Atomära egenskaper

Electronegativity (Pauling Scale)1.28
Electron affinity-48.33 kJ/mol
Ionization energies
1584.7 kJ/mol

Electron configuration

Electron configuration1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 4f14 5s2 5p6 5d10 5f6 6s2 6p6 7s2
Electrons per shell2, 8, 18, 32, 24, 8, 2


Discovered byGlenn T. Seaborg
Arthur Wahl
Joseph W. Kennedy
Edwin McMillan