Francium
Alkali Metal
Francium (Fr) is a chemical element with atomic number 87, classified as a alkali metal. At room temperature it is a solid. It was discovered in 1939 by Marguerite Perey.
Properties
- Atomic number
- 87
- Atomic mass
- 223 u
- Category
- Alkali Metal
- Group
- 1
- Period
- 7
- Block
- s-block
- Electron configuration
- [Rn] 7s¹
- Phase at STP
- Solid
- Density
- 1.87 g/cm³
- Melting point
- 300 K (26.9 °C)
- Boiling point
- 950 K (676.9 °C)
- Electronegativity
- 0.7
- Atomic radius
- 348 pm
- Ionization energy
- 4.073 eV
- Discovery
- 1939 · Marguerite Perey
Common uses
Research only
Did you know?
Most unstable of the first 101 elements with half-life of 22 minutes.
Experiment with the elements
Francium doesn't form any compounds in our lab yet, but the periodic table sandbox lets you combine dozens of other real elements into real compounds — water, table salt, ammonia and many more — with their true chemical formulas.