Polonium, 84PoPolonium |
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Pronunciation | (pə-LOH-nee-əm) |
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Appearance | sillery |
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Mass number | [209] |
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Polonium in the periodic cairt |
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Atomic nummer (Z) | 84 |
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Group | group 16 (chalcogens) |
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Period | period 6 |
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Block | p-block |
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Element category | Post-transeetion metal |
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Electron confeeguration | [Xe] 4f14 5d10 6s2 6p4 |
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Electrons per shell | 2, 8, 18, 32, 18, 6 |
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Pheesical properties |
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Phase at STP | solit |
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Meltin pynt | 527 K (254 °C, 489 °F) |
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Bylin pynt | 1235 K (962 °C, 1764 °F) |
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Density (near r.t.) | (alpha) 9.196 g/cm3 (beta) 9.398 g/cm3 |
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Heat o fusion | ca. 13 kJ/mol |
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Heat o vapourisation | 102.91 kJ/mol |
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Molar heat capacity | 26.4 J/(mol·K) |
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Vapour pressur
P (Pa)
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1
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10
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100
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1 k
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10 k
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100 k
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at T (K)
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|
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(846)
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1003
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1236
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Atomic properties |
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Oxidation states | −2, +2, +4, +5,[1] +6 (an amphoteric oxide) |
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Electronegativity | Pauling scale: 2.0 |
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Atomic radius | empirical: 168 pm |
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Covalent radius | 140±4 pm |
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Van der Waals radius | 197 pm |
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Spectral lines o polonium |
Ither properties |
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Creestal structur | cubic |
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Thermal expansion | 23.5 µm/(m·K) (at 25 °C) |
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Thermal conductivity | ? 20 W/(m·K) |
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Electrical resistivity | (α) 0.40 µ Ω·m (at 0 °C) |
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Magnetic orderin | nonmagnetic |
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CAS Nummer | 7440-08-6 |
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History |
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Diskivery | Pierre Curie an Marie Curie (1898) |
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First isolation | Willy Marckwald (1902) |
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Main isotopes o polonium |
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| references |
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in
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calc from C
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report
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ref
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C
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254
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—
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—
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K
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527
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527
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0
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F
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489
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489
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0
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WD
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String Module Error: Target string is empty !
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input
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C: 254, K: 527, F: 489
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comment
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in
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calc from C
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diff
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report
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ref
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C
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962
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—
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—
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K
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1235
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1235
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0
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F
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1764
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1764
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0
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WD
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String Module Error: Target string is empty !
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input
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C: 962, K: 1235, F: 1764
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comment
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References
Thir references will appear in the airticle, but this list appears anerly on this page.
- ↑ Thayer, John S. (2010). "Relativistic Effects and the Chemistry of the Heavier Main Group Elements". Relativistic Methods for Chemists: 78. doi:10.1007/978-1-4020-9975-5_2. ISBN 978-1-4020-9974-8.
- ↑ Thayer, John S. (2010). Chemistry of heavier main group elements. p. 78. doi:10.1007/9781402099755_2.