rubidium

Symbol: Rb
Atomic number: 37
Atomic weight: 85.4678
Group: 1
Group name: Alkali metal
Period: 5
Block: s
CAS ID: 7440-17-7
Shell structure: 2.8.18.8.1
Electron configuration: [Kr].5s1
State: |standardstate|
Melting point: 312.46 [or 39.31 °C (102.76 °F)]
Boiling point: 961 [or 688 °C (1270 °F)]
Ionization energy/kJ per mol: 403.0
Common oxidation states: 1
Pauling electronegativity: 0.82