55

Cs

Cesium

132.91

Alkali Metal
Solid

Discovery

Kirchhoff, Gustav & Bunsen, Robert (1860)

Etymology

Latin

Meaning

Blue-grey

Electron configuration

Electron configuration

Crystal structure

Crystal structure

Body-centered cubic

Physical Properties

Phase

  (at 21 °C and 101.325 kPa)

Solid

Melting point

  (at 101.325 kPa)

29.0 °C

302.15 K

Boiling point

  (at 101.325 kPa)

-108.0 °C

165.15 K

Density

  (at 21 °C and 101.325 kPa)

1.87 g/cm3

Electronegativity

0.79