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Radium

88
Ra
226.0254
Radium
 General | States | Energies | Oxidation & Electrons | Appearance & Characteristics | Reactions | Other Forms Radius | Conductivity | Abundance

General:

Name: Radium Symbol: Ra
Group: Alkali Earth Atomic weight: 226.0254
Density @ 293 K: 5 g/cm3 Atomic volume: 45.20 cm3/mol
Group: Alkali Earth discovered: 1898

States:

state (s, l, g): s
melting point: 973.2 K boiling point: 1973 K
Heat of fusion: ? Heat of vaporization: ?

Energies:

1st ionization energy: 509.4 kJ/mole
electronegativity: 0.9 2nd ionization energy: 979.1 kJ/mole
electron affinity: kJ/mole 3rd ionization energy: kJ/mole
Specific heat: 0.12 J/gK heat atomization: 159 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,32,18,8,2 electron configuration: [Rn] 7s2
minimum oxidation number: 0 maximum oxidation number: 2
min. common oxidation no.: 0 max. common oxidation no.: 2

Appearance & Characteristics:

structure: bcc: body-centered cubic color: white
uses: neutron source toxicity:
hardness: mohs characteristics: Radioactive, luminescent

Reactions:

reaction with air: vigorous, =>RaO2, Ra3N2
reaction with 6M HCl: reaction with 6M HCl:
reaction with 15M HNO3: reaction with 6M NaOH:

Other Forms:

number of isotopes: 4 hydride(s):
oxide(s): chloride(s): RaCl2

Radius:

ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: pm ionic radius (1+ ion): pm
ionic radius (2+ ion): 162 pm ionic radius (3+ ion): pm

Conductivity:

thermal conductivity: 18.6 J/m-sec-deg
electrical conductivity: 1/mohm-cm polarizability: 38.3 A^3

Abundance:

source: pitchblende(U-238 decay)
rel. abund. solar system: log abundance earth's crust: -6 log
cost, pure: $/100g cost, bulk: $/100g