Periodex

General properties

Group

n/a

Period

period 7

Category

actinoids

Standard atomic weight

-

Melting point

1800 K (predicted)

Boiling point

unknown

Phase at STP

solid (predicted)

Additional properties

Block

f-block

Electron configuration

[Rn] 5f¹² 7s²

Electrons per shell

2, 8, 18, 32, 30, 8, 2

Electronegativity

1.3

Density

9.7(1) g/cm³ (predicted)

Oxidation states

+2, +3

CAS Number

7440-72-4

Natural isotopes

Discovery history

Discovered by

Lawrence Berkeley National Laboratory

Year of discovery

1952

Origin of name

Enrico Fermi, physicist