87Fr
Francium
프랑슘 · フランシウム
Alkali metal
Atomic number87
ElementFr — Francium
Atomic mass223
CategoryAlkali metal
Group1
Period7
Electron config[Rn] 7s1
Shells2,8,18,32,18,8,1
State (RT)Solid
Melting pt27°C
Boiling pt677°C
Electronegativity0.7
Discovered1939
Main usesResearch only
2 · 8 · 18 · 32 · 18 · 8 · 1