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Atomic: M.A.C. | Reference
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Radium
Electrons per shell 2,8,18,32,18,8,2
Electron Configuration [Rn] 7s2 open electron config
Ground state 1S0
Atomic Volume 45.2 cm3 mol-1
Electronegativity 0.9
Magnetic ordering Non-magnetic
Thermal Properties
Enthalpy of Atomization 163 kJ mol-1 @25°C
Enthalpy of Fusion 7.15 kJ mol-1
Enthalpy of Vaporisation 136.7 kJ mol-1
Heat Capacity No data.
Thermal Conductivity 18.6 W m-1 K-1
Thermal Expansion No data.
Electrical Properties
Electrical resistivity 1.00 x 10-6 Ω m
Electrical conductivity ? 106/cm Ω
Chemical Properties
Electrochemical Equivalent 4.2165 g Ah-1
Valence Electron Potential (-eV) 20.1
Ionization Potential  
First 5.279
Second 10.148
Energy Levels
Kα1 (intensity 0) 88.47 KeV
Kα2 (intensity 0) 85.43 KeV
Kβ1 (intensity 0) 100.13 KeV
Lα1 (intensity 100) 12.3397 KeV
Lα2 (intensity 10) 12.1962 KeV
Lβ1 (intensity 38) 15.2358 KeV
Lβ2 (intensity 14) 14.8414 KeV
Lβ3 (intensity 2) 15.4436 KeV
Lβ4 (intensity 2) 14.7465 KeV
Lγ1 (intensity 8) 17.849 KeV
Lγ2 (intensity 2.7) 18.1708 KeV
Lγ3 (intensity 2) 13.658 KeV
Ll (intensity 6) 10.6247 KeV
Atomic Radii
Empirical 215 pm
Bohr Radius No data.
Covalent Radius No data.
Van der Waals No data.
Triple covalent 159 pm
Metallic No data.
Oxidation States
Main Ra+2
Other
Ionisation Energies (kJ mol-1) show graph
M - M+ 509.3
M+ - M2+ 979
M2+ - M3+ 3300
M3+ - M4+ 4400
M4+ - M5+ 5700
M5+ - M6+ 7300
M6+ - M7+ 8600
M7+ - M8+ 9900
M8+ - M9+ 13500
M9+ - M10+ 15100
Vapour Pressure
P (Pa) 1 10 100 1K 10K 100K
T (K) 819 906 1037 1209 1446 1799
Crystal Structure
Structure Body centred cubic
a = 514.8 pm
b = 514.8 pm
c = 514.8 pm
α = 90°
β = 90°
γ = 90°