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Radium (Ra)
Atomic number: 88 · Category: alkaline earth metal · Group 2 · Period 7 · Phase: Solid
Radium is a chemical element with symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is almost colorless, but it readily combines with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2).
Atomic mass: 226
Density: 5.5
Melting point: 1233 K
Boiling point: 2010 K
Appearance: silvery white metallic
Source: Wikipedia
Block: s
CPK color:#007d00
Electronic structure
Electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2
Configuration (semantic): [Rn] 7s2
Shells: 2, 8, 18, 32, 18, 8, 2
Electronegativity (Pauling): 0.9
Electron affinity: 9.6485
Ionization energies: 509.3, 979
Periodic position
Group: 2
Period: 7
xpos: 2
ypos: 7
Spectral/Bohr images
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3D Model