Symbol
Fr
Atomic Number
87
Atomic Mass
223
Protons
87
Neutrons
136
Electrons
87
Type
Alkali Metal
Isotopes
Francium-223
Discovery Year
1939
Discovered By
Marguerite Perey
Group
1
Period
7
Boiling Point
678°C
Melting Point
27°C
Electron Configuration
[Rn] 7s¹
Density (g/cm³)
0.87
Crystal Structure
Cubic
Magnetism
Diamagnetic
Abundance in Earth's Crust
Trace
Phase at Room Temperature
Solid