Radium

Alkaline earth metal · 226.02541 u · group 2, period 7

Radium · Ra

Atomic number88

SymbolRa

CategoryAlkaline earth metal

Standard stateSolid

Group · Period · Block2 · 7 · s

Electron configuration[Rn]7s2

Atomic mass226.02541 u

Atomic radius283 pm

Protons / Neutrons / Electrons88 / 138 / 88

Shells (e⁻ per shell)2, 8, 18, 32, 18, 8, 2

Electronegativity (Pauling)0.9

Ionization energy5.279 eV

Electron affinity—

Oxidation states+2

Melting point973 K · 699.9 °C

Boiling point1.41e+3 K · 1.14e+3 °C

Density5 g/cm³

Year discovered1898

CPK color

#007D00

State at room temp (25 °C)

solid

Position