Plutonium was discovered by Glenn T. Seaborg , J. W. Kennedy, E. M. McMillan, A. C. Wahl at 1940 in USA.
Origin of name: named after "the planet Pluto".
Atomic Number: 94
Atomic Weight: 244
Melting Point: 913 K (640°C or 1184°F)
Boiling Point: 3501 K (3228°C or 5842°F)
Density: 19.84 grams per cubic centimeter
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 7 Group Number: none Group Name: Actinide