Periodex

General properties

Group

n/a

Period

period 7

Category

actinoids

Standard atomic weight

-

Melting point

1133 K (860 °C)

Boiling point

1269 K (996 °C)

Phase at STP

solid

Additional properties

Block

f-block

Electron configuration

[Rn] 5f¹¹ 7s²

Electrons per shell

2, 8, 18, 32, 29, 8, 2

Electronegativity

1.3

Density

8.84 g/cm³

Oxidation states

+2, +3, +4

CAS Number

7429-92-7

Natural isotopes

Discovery history

Discovered by

Lawrence Berkeley National Laboratory

Year of discovery

1952

Origin of name

Albert Einstein, physicist