NO. 037Alkali

Rb

Rubidium

Rubidium is a very reactive Alkali used in research and atomic clocks.

Crystal Structure

Body-centered cubic (bcc)

Atomic Mass85.47 u

Density1.53 g/cm³

Melting Point312 K

Boiling Point961 K

Atomic Radius265 pm

Electronegativity0.82

Ionization Energy403 kJ/mol

Electron Affinity47 kJ/mol

Bonding TypeMetallic

Oxidation States1

Acid/BaseBasic

ReactivityHigh

Electron Configuration

[Kr] 5s1

Discovered ByRobert Bunsen

Year1861

Known Isotopes

Rb-85Rb-87