General: |
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Name: Promethium
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Symbol: Pm
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Group: Rare Earth, Lanthanides
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Atomic weight: (145)
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Density @ 293 K: 6.475 g/cm3
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Atomic volume: 22.39 cm3/mol
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Group: Rare Earth, Lanthanides
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discovered: 1945
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States: |
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state (s, l, g): s
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melting point: 1353.2 K
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boiling point: 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: 535.9 kJ/mole
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electronegativity: 1.15
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2nd ionization energy: 1052 kJ/mole
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electron affinity: 50 kJ/mole
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3rd ionization energy: 2150 kJ/mole
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Specific heat: 0.18 J/gK
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heat atomization: 301 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,18,23,8,2
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electron configuration: [Xe] 4f5 6s2
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minimum oxidation number: 0
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maximum oxidation number: 3
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min. common oxidation no.: 0
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max. common oxidation no.: 3
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Appearance & Characteristics: |
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structure: cp: close packed (ABCB)
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color: silvery-white
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uses: nuclear battery
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toxicity:
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hardness: mohs
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characteristics: Radioactive
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Reactions: |
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reaction with air: vigorous, =>Pm2O3
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reaction with 6M HCl: mild, =>H2, PmCl3
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reaction with 6M HCl: mild, =>H2, PmCl3
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reaction with 15M HNO3: mild, =>Pm(NO3)3
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reaction with 6M NaOH:
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Other Forms: |
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number of isotopes: 0
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hydride(s):
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oxide(s): Pm2O3
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chloride(s):
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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: 183 pm
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ionic radius (1+ ion): pm
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ionic radius (2+ ion): pm
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ionic radius (3+ ion): 111 pm
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Conductivity: |
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thermal conductivity: 17.9 J/m-sec-deg
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electrical conductivity: 1/mohm-cm
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polarizability: 30.1 A^3
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Abundance: |
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source: Synthetic
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rel. abund. solar system: log
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abundance earth's crust: -19.3 log
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cost, pure: $/100g
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cost, bulk: $/100g
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