General: |
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Name: Praseodymium
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Symbol: Pr
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Group: Rare Earth, Lanthanides
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Atomic weight: 140.9077
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Density @ 293 K: 6.77 g/cm3
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Atomic volume: 20.8 cm3/mol
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Group: Rare Earth, Lanthanides
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discovered: 1885
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States: |
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state (s, l, g): s
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melting point: 1204.2 K
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boiling point: 3293 K
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Heat of fusion: 6.890 kJ/mol
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Heat of vaporization: 296.80 kJ/mol
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Energies: |
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1st ionization energy: 523.2 kJ/mole
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electronegativity: 1.13
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2nd ionization energy: 1018 kJ/mole
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electron affinity: 50 kJ/mole
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3rd ionization energy: 2086 kJ/mole
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Specific heat: 0.19 J/gK
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heat atomization: 356 kJ/mole atoms
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Oxidation & Electrons: |
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Shells: 2,8,18,21,8,2
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electron configuration: [Xe] 4f3 6s2
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minimum oxidation number: 0
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maximum oxidation number: 4
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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: alloys, Welder's mask
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toxicity:
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hardness: mohs
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characteristics: soft
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Reactions: |
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reaction with air: vigorous, =>Pr6O11 approx
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reaction with 6M HCl: mild, =>H2, PrCl3
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reaction with 6M HCl: mild, =>H2, PrCl3
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reaction with 15M HNO3: mild, =>Pr(NO3)3
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reaction with 6M NaOH:
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Other Forms: |
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number of isotopes: 1
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hydride(s): PrH2 PrH3
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oxide(s): PrO2 Pr6O11
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chloride(s): PrCl3
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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: 182 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): 113 pm
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Conductivity: |
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thermal conductivity: 12.5 J/m-sec-deg
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electrical conductivity: 14.706 1/mohm-cm
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polarizability: 28.2 A^3
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Abundance: |
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source: Monazite(phosphate),bastnaesite
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rel. abund. solar system: -0.778 log
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abundance earth's crust: 0.9 log
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cost, pure: 170 $/100g
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cost, bulk: $/100g
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