Periodic Table
37
Rb
85.468
Rubidium
Alkali MetalVery reactive; red-violet flame; ignites in air.
Electronic Configuration
[Kr] 5s¹or1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹
Electron shells
2e⁻n=1
8e⁻n=2
18e⁻n=3
8e⁻n=4
1e⁻n=5
Properties
Atomic number
37
Atomic mass
85.468 u
Category
Alkali Metal
Block / Group / Period
s · 1 · 5
Valence electrons
1
Oxidation states
+1
Electronegativity
0.82
Atomic radius
265 pm
Ionization energy
403 kJ/mol
Electron affinity
47 kJ/mol
Melting point
312 K / 39 °C
Boiling point
961 K / 688 °C
Density
1.532 g/cm³
State at 25 °C
solid
Personal Notes
Add personal notes for Rubidium here...