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Francium (Fr) - Properties


Atomic mass, symbol and atomic number

francium is a naturally occurring element with the element symbol Fr and the atomic number 87. In the periodic table it stands with an atomic mass of 223.019 u in the 1st main group. The chemical element discovered by Marguerite Perey in 1939 is radioactive and is in a solid state of aggregation at room temperature.

Profile: Francium (English Francium)

General
Chemical element:francium
Symbol:Fri.
Atomic number:87
Group:Alkali metal group
Period:7
Block:s block
Series:alkali metals
Appearance:unknown
explorers:Marguerite Perey
Year of discovery:1939
Atomic properties
Atomic mass:223,019 u
Atomic radius:???
Covalent radius:260 pm
Van der Waals radius:348 pm
Electron configuration:Rn 7s1
ionization:380 kJ / mol
Physical Properties
Physical state:firmly
Density:1.87 g · cm-3
Crystal structure:cubic
Magnetism:paramagnetic
molar volume:unknown
Mohs hardness:unknown
Melting point:27 ° C
Boiling point:677 ° C
Heat of fusion:unknown
Heat of vaporization:unknown
Thermal conductivity:unknown
Chemical properties
electronegativity:0,7

Did you know that ...

  • Francium after Astat is the second-oldest element on earth?
  • the element was named after the home country (France) of the discoverer Marguerite Perey?
  • Francium has no economic significance because of its rarity?