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Rubidium (Rb)
Atomic number: 37 · Category: alkali metal · Group 1 · Period 5 · Phase: Solid
Rubidium is a chemical element with symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group, with an atomic mass of 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other alkali metals, such as very rapid oxidation in air.
Atomic mass: 85.46783
Density: 1.532
Melting point: 312.45 K
Boiling point: 961 K
Appearance: grey white
Source: Wikipedia
Block: s
Molar heat: 31.06
CPK color:#702eb0
Electronic structure
Electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1
Configuration (semantic): [Kr] 5s1
Shells: 2, 8, 18, 8, 1
Electronegativity (Pauling): 0.82
Electron affinity: 46.884
Ionization energies: 403, 2633, 3860, 5080, 6850, 8140, 9570, 13120, 14500, 26740
Periodic position
Group: 1
Period: 5
xpos: 1
ypos: 5
Spectral/Bohr images
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3D Model