General: |
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Name: Radium
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Symbol: Ra
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Group: Alkali Earth
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Atomic weight: 226.0254
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Density @ 293 K: 5 g/cm3
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Atomic volume: 45.20 cm3/mol
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Group: Alkali Earth
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discovered: 1898
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States: |
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state (s, l, g): s
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melting point: 973.2 K
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boiling point: 1973 K
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Heat of fusion: ?
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Heat of vaporization: ?
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Energies: |
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1st ionization energy: 509.4 kJ/mole
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electronegativity: 0.9
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2nd ionization energy: 979.1 kJ/mole
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electron affinity: kJ/mole
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3rd ionization energy: kJ/mole
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Specific heat: 0.12 J/gK
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heat atomization: 159 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,18,32,18,8,2
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electron configuration: [Rn] 7s2
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minimum oxidation number: 0
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maximum oxidation number: 2
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min. common oxidation no.: 0
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max. common oxidation no.: 2
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Appearance & Characteristics: |
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structure: bcc: body-centered cubic
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color: white
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uses: neutron source
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toxicity:
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hardness: mohs
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characteristics: Radioactive, luminescent
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Reactions: |
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reaction with air: vigorous, =>RaO2, Ra3N2
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reaction with 6M HCl:
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reaction with 6M HCl:
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reaction with 15M HNO3:
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reaction with 6M NaOH:
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Other Forms: |
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number of isotopes: 4
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hydride(s):
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oxide(s):
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chloride(s): RaCl2
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Radius: |
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ionic radius (2- ion): pm
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ionic radius (1- ion): pm
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atomic radius: pm
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ionic radius (1+ ion): pm
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ionic radius (2+ ion): 162 pm
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ionic radius (3+ ion): pm
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Conductivity: |
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thermal conductivity: 18.6 J/m-sec-deg
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electrical conductivity: 1/mohm-cm
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polarizability: 38.3 A^3
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Abundance: |
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source: pitchblende(U-238 decay)
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rel. abund. solar system: log
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abundance earth's crust: -6 log
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cost, pure: $/100g
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cost, bulk: $/100g
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