Wir sind führender Hersteller und Lieferant von Forschungsmaterialien
1861 von R.W. Bunsen und G. Kirchhoff an der Universität Heidelberg, Deutschland, entdeckt.
[Lateinisch, rubidius = dunkelrot]
French: rubidium
English: rubidium
Italian: rubidio
Spanish: rubidio
Beschreibung: Sehr weiches Metall, frische Schnittflächen sind glänzend silberweiß. Entzündet sich an Luft und reagiert heftig mit Wasser. Außer in der Forschung wenig verwendet.
Crystal structure: |
(cell dimensions/pm), space group, |
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X-ray diffractions mass absorption coefficients: | CuKa 117 (µ/r) / cm2g-1 MoKa 90 (µ/r) / cm2g-1 |
Neutron scattering length: | 0.709 b/10-12 cm |
Thermal neutron capture cross-section: | 0.38 sa / barns |
Density: | 1532 kg/m-3 [293 K]; 1475 [liquid at m.p.] |
Melting point: | 39.05°C / 312.2°K |
Boiling point: | 687.85°C / 961°K |
Molar volume: | 55.79 cm3 |
Thermal conductivity: | 58.2 [300 K] W m-1K-1 |
Coefficient of linear thermal expansion: | 90 x 10-6 K-1 |
Electrical resistivity: | 12.5 x 10-8 [293 K] Ωm |
Mass magnetic susceptibility: | +2.49 x 10-9(s) kg-1m3 |
Radi: | Rb+ 149; atomic 247.5; van der Waals 244 |
Electronegativity: | 0.82 (Pauling); 0.89 (Allred); 2.34 eV (absolute) |
Effective nuclear charge: | 2.20 (Slater); 4.98 (Clementi); 6.66 (Froese-Fischer) |
Number of Isotopes (incl. nuclear isomers): | 30 |
Isotope mass range: | 75 -> 98 |
Biological role: | Rubidium has no known role; its salts have a stimulatory effect. |
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Toxicity | |
Toxic intake: | can be toxic by ingestion. |
Lethal intake: | LD50 (chloride, oral, mouse) = 3800 mg kg-1 |
Hazards: | Rubidium salts are generally inert, and their toxicity is almost always that of the anion, not of the Rb+. However, in the body, rubidium substitutes for potassium and too much can be dangerous. |
Level in humans | |
Blood: | 2.49 mg dm-3 |
Bone: | 0.1 - 5 ppm |
Liver: | 20 - 70 ppm |
Muscle: | 20 - 70 ppm |
Daily dietary intake: | 1.5 - 6 mg |
Total mass of element in average [70 kg] person: |
680 mg |
Minerals: No minerals as such are known, but rubidium is present in significant amounts in lepidolite (see lithium), pollucite(see caesium) and carnallite (see potassium).
World production: | n.a. |
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Reserves: | n.a. |
Specimen: | available as ingots in sealed ampoules. Danger! |
Abundances | |
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Sun: | 400 (relative to H = 1 x 1012) |
Earth's crust: | 90 ppm |
Seawater | 0.12 ppm |
Residence time: | 800 000 years |
Classification: | accumulating |
Oxidation state: | I |
Source: Emsley, J. (1998) The Elements (3rd Edition)
Other sizes and specifications on request