- Atomic Radius (Å)
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.
55 Atomic Number
132.91 u Atomic Mass
301.7 K Melting Point
944 K Boiling Point
1.93 g/cm³ Density
3.3 Å Atomic Radius
2.44 Å Covalent Radius
0.79 Electronegativity
3.89 eV First Ionization Energy
45.51 Electron Affinity
6 Number of Shells
1 Electron Valency
2, 8, 18, 18, 8, 1 Electron Shell Occupations
0.24 J/g Specific Heat