- Temp: comparing dataset and input-parameter here to check. No effect in article. [January 2019]
- DIFF
- (parameter is empty) -- infobox
- [Rn] 7s1 -- dataset
- Using symb-to-elconfig dataset now. DIFFs marked here may be caused by technical issues wrt reference handling, not actual diffs. -DePiep (talk) 20:17, 3 February 2019 (UTC)
Francium, 87Fr|
Pronunciation | (FRAN-see-əm) |
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Mass number | 223 (most stable isotope) |
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|
|
Atomic number (Z) | 87 |
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Group | group 1 (alkali metals) |
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Period | period 7 |
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Block | s-block |
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Element category | alkali metal |
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Electron configuration | [Rn] 7s1 |
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Electrons per shell | 2, 8, 18, 32, 18, 8, 1 |
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|
Phase at STP | Fr: Solid |
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Melting point | 300 K (27 °C, 81 °F) |
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Boiling point | 950 K (677 °C, 1251 °F) |
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Density (near r.t.) | 2.48 g/cm3 (estimated)[1] |
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Vapor pressure (extrapolated)
P (Pa)
|
1
|
10
|
100
|
1 k
|
10 k
|
100 k
|
at T (K)
|
404
|
454
|
519
|
608
|
738
|
946
|
|
|
Oxidation states | +1 (a strongly basic oxide) |
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Electronegativity | Pauling scale: >0.79 |
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Ionization energies | |
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Covalent radius | 260 pm (extrapolated) |
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Van der Waals radius | 348 pm (extrapolated) |
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Natural occurrence | Fr: From decay |
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Crystal structure | body-centered cubic (bcc) (extrapolated) |
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Thermal conductivity | 15 W/(m·K) (extrapolated) |
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Electrical resistivity | 3 µΩ·m (calculated) |
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Magnetic ordering | Paramagnetic |
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CAS Number | 7440-73-5 |
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|
Naming | after France, homeland of the discoverer |
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Discovery and first isolation | Marguerite Perey (1939) |
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|
|
| references |
References
This reference list does not appear in the article.
- ↑ Lavrukhina, Avgusta Konstantinovna; Pozdnyakov, Aleksandr Aleksandrovich (1970). Analytical Chemistry of Technetium, Promethium, Astatine, and Francium. Translated by R. Kondor. Ann Arbor–Humphrey Science Publishers. p. 269. ISBN 978-0-250-39923-9.
- ↑ ISOLDE Collaboration, J. Phys. B 23, 3511 (1990) (PDF online)