Rb
Rubidium
Alkali MetalAtomic Number: 37 • Atomic Mass: 85.4680 u • Period: 5 • Group: 1
Electron Configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹
Phase: Solid
Electronegativity: 0.82
History
Rubidium has been known since ancient times
Historical Timeline
Discovered using spectroscopy in mineral lepidolite
Named for the deep red color of its spectral lines
Pure metal isolated by George de Hevesy in 1928