HHomeBackground Color:He
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NaMgRadium Pictures PageAlSiPSClAr
KCaRadium Isotope DataScTiVCrMnFeCoNiCuZnGaGeAsSeBrKr
RbSrYZrNbMoTcRuRhPdAgCdInSnSbTeIXe
CsBaLaCePrNdPmSmEuGdTbDyHoErTmYbLuHfTaWReOsIrPtAuHgTlPbBiPoAtRn
FrRaAcThPaUNpPuAmCmBkCfEsFmMdNoLrRfDbSgBhHsMtDsRgCnNhFlMcLvTsOg

Technical data for Radium

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

Overview
NameRadium
SymbolRa
Atomic Number88
Atomic Weight226[note]
Density5 g/cm3
Melting Point700 °C
Boiling Point1737 °C

Thermal properties
PhaseSolid
Melting Point700 °C
Boiling Point1737 °C
Absolute Melting Point973 K
Absolute Boiling Point2010 K
Critical PressureN/A
Critical TemperatureN/A
Heat of Fusion8 kJ/mol
Heat of Vaporization125 kJ/mol
Specific Heat92 J/(kg K)[note]
Adiabatic IndexN/A
Neel PointN/A
Thermal Conductivity19 W/(m K)
Thermal ExpansionN/A

Bulk physical properties
Density5 g/cm3
Density (Liquid)N/A
Molar Volume0.0000452
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 Conductivity19 W/(m K)
Thermal ExpansionN/A

Reactivity
Valence2
Electronegativity0.9
ElectronAffinityN/A
Ionization Energies
509.3, 979 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
Group2
Period7
SeriesAlkaline Earth Metal
Electron Configuration[Rn]7s2
ColorSilver
Discovery
1898 in France
Gas phaseN/A
CAS NumberCAS7440-14-4
CID Number
CID6328144
RTECS NumberN/A

Electrical properties
Electrical TypeConductor
Electrical Conductivity1×106 S/m
Resistivity1×10-6 m Ω
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 Crust1×10-11%
% in Oceans1×10-15%
% in Humans1×10-13%

Atomic dimensions and structure
Atomic RadiusN/A
Covalent Radius221 pm
Van der Waals RadiusN/A
Crystal StructureBody-centered Cubic
Lattice Angles
π/2, π/2, π/2
Lattice Constants
514.8, 514.8, 514.8 pm
Space Group NameIm_ 3m
Space Group Number229

Nuclear Properties
Half-Life1585.489599188 y
Lifetime2314.814814815 y
Decay ModeAlphaEmission
Quantum Numbers1S0
Neutron Cross Section13
Neutron Mass AbsorptionN/A
Known Isotopes
202Ra, 203Ra, 204Ra, 205Ra, 206Ra, 207Ra, 208Ra, 209Ra, 210Ra, 211Ra, 212Ra, 213Ra, 214Ra, 215Ra, 216Ra, 217Ra, 218Ra, 219Ra, 220Ra, 221Ra, 222Ra, 223Ra, 224Ra, 225Ra, 226Ra, 227Ra, 228Ra, 229Ra, 230Ra, 231Ra, 232Ra, 233Ra, 234Ra
Stable Isotopes
None
Isotopic Abundances


Notes on the properties of Radium:

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

Specific Heat: Value given for gas phase.

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

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