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Cesium (Cs)
Atomic number: 55 · Category: alkali metal · Group 1 · Period 6 · Phase: Solid
Caesium or cesium is a chemical element with symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28 °C (82 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium is an alkali metal and has physical and chemical properties similar to those of rubidium and potassium.
Atomic mass: 132.905451966
Density: 1.93
Melting point: 301.7 K
Boiling point: 944 K
Appearance: silvery gold
Source: Wikipedia
Block: s
Molar heat: 32.21
CPK color:#57178f
Electronic structure
Electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s1
Configuration (semantic): [Xe] 6s1
Shells: 2, 8, 18, 18, 8, 1
Electronegativity (Pauling): 0.79
Electron affinity: 45.505
Ionization energies: 375.7, 2234.3, 3400
Periodic position
Group: 1
Period: 6
xpos: 1
ypos: 6
Spectral/Bohr images
Image
3D Model