Strontium

Alkaline earth metal · 87.62 u · group 2, period 5

Strontium · Sr

Atomic number38

SymbolSr

CategoryAlkaline earth metal

Standard stateSolid

Group · Period · Block2 · 5 · s

Electron configuration[Kr]5s2

Atomic mass87.62 u

Atomic radius249 pm

Protons / Neutrons / Electrons38 / 50 / 38

Shells (e⁻ per shell)2, 8, 18, 8, 2

Electronegativity (Pauling)0.95

Ionization energy5.695 eV

Electron affinity—

Oxidation states+2

Melting point1.05e+3 K · 776.9 °C

Boiling point1.66e+3 K · 1.38e+3 °C

Density2.64 g/cm³

Year discovered1790

CPK color

#00FF00

State at room temp (25 °C)

solid

Position