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KCaFrancium Isotope DataScTiVCrMnFeCoNiCuZnGaGeAsSeBrKr
RbSrYZrNbMoTcRuRhPdAgCdInSnSbTeIXe
CsBaLaCePrNdPmSmEuGdTbDyHoErTmYbLuHfTaWReOsIrPtAuHgTlPbBiPoAtRn
FrRaAcThPaUNpPuAmCmBkCfEsFmMdNoLrRfDbSgBhHsMtDsRgCnNhFlMcLvTsOg

Technical data for Francium

Click any property name to see plots of that property for all the elements.

Overview
NameFrancium
SymbolFr
Atomic Number87
Atomic Weight223[note]
DensityN/A
Melting PointN/A
Boiling PointN/A

Thermal properties
PhaseSolid
Melting PointN/A
Boiling PointN/A
Absolute Melting PointN/A
Absolute Boiling PointN/A
Critical PressureN/A
Critical TemperatureN/A
Heat of Fusion2 kJ/mol
Heat of Vaporization64 kJ/mol
Specific HeatN/A
Adiabatic IndexN/A
Neel PointN/A
Thermal ConductivityN/A
Thermal ExpansionN/A

Bulk physical properties
DensityN/A
Density (Liquid)N/A
Molar VolumeN/A
Brinell HardnessN/A
Mohs HardnessN/A
Vickers HardnessN/A
Bulk ModulusN/A
Shear ModulusN/A
Young ModulusN/A
Poisson RatioN/A
Refractive IndexN/A
Speed of SoundN/A
Thermal ConductivityN/A
Thermal ExpansionN/A

Reactivity
Valence1
Electronegativity0.7
ElectronAffinityN/A
Ionization Energies
380 kJ/mol

Health and Safety
DOT Hazard ClassN/A
DOT NumbersN/A
RTECS NumberN/A
NFPA LabelN/A

Classifications
Alternate NamesNone
Names of AllotropesNone
Blocks
Group1
Period7
SeriesAlkali Metal
Electron Configuration[Rn]7s1
ColorSilver
Discovery
1939 in France
Gas phaseN/A
CAS NumberCAS7440-73-5
CID NumberN/A
RTECS NumberN/A

Electrical properties
Electrical TypeN/A
Electrical ConductivityN/A
ResistivityN/A
Superconducting PointN/A

Magnetic properties
Magnetic TypeN/A
Curie PointN/A
Mass Magnetic SusceptibilityN/A
Molar Magnetic SusceptibilityN/A
Volume Magnetic SusceptibilityN/A

Abundances
% in UniverseN/A
% in SunN/A
% in MeteoritesN/A
% in Earth's CrustN/A
% in OceansN/A
% in Humans0%

Atomic dimensions and structure
Atomic RadiusN/A
Covalent Radius260 pm
Van der Waals RadiusN/A
Crystal StructureN/A
Lattice AnglesN/A
Lattice ConstantsN/A
Space Group NameN/A
Space Group NumberN/A

Nuclear Properties
Half-Life21.66666666667 m
Lifetime31.66666666667 m
Decay ModeBetaDecay
Quantum Numbers2S1/2
Neutron Cross SectionN/A
Neutron Mass AbsorptionN/A
Known Isotopes
199Fr, 200Fr, 201Fr, 202Fr, 203Fr, 204Fr, 205Fr, 206Fr, 207Fr, 208Fr, 209Fr, 210Fr, 211Fr, 212Fr, 213Fr, 214Fr, 215Fr, 216Fr, 217Fr, 218Fr, 219Fr, 220Fr, 221Fr, 222Fr, 223Fr, 224Fr, 225Fr, 226Fr, 227Fr, 228Fr, 229Fr, 230Fr, 231Fr, 232Fr
Stable Isotopes
None
Isotopic Abundances


Notes on the properties of Francium:

Atomic Mass: Atomic mass number given for longest lived isotope.

Up to date, curated data provided by Mathematica's ElementData function from Wolfram Research, Inc.

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