Wir sind führender Hersteller und Lieferant von Forschungsmaterialien
1803 von W.H. Wollaston in London, UK, entdeckt.
[Nach dem Asteroiden Pallas benannt]
French: palladium
English: palladium
Italian: palladio
Spanish: palladio
Beschreibung: Silberweißes Metall, glänzend, verformbar, duktil. Korrodiert nicht, löst sich in oxidierenden Säuren und geschmolzenen Alkalien. Absorbiert leicht Wasserstoffgas. Hauptsächlich als Katalysator verwendet.
State: | single crystal |
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Crystal structure: | fcc |
Production method: | Czochralski |
Standard size: | diameter 6-12mm thickness 1-2mm |
Orientation: | (100), (110) and (111) |
Orientation accuracy: | <2°, <1°, <0.4° or <0.1° |
Polishing: | as cut, one or two sides polished |
Roughness of surface: | <0.03µm |
Purity: | 99.999% |
Typical analysis (ppm): | C 3 H < 1 O 9 N < 5 Cu 1.60 Fe 1.80 Ni < 1 Pb 0.30 Si 0.30 Ga, Hf and Ta are below the detection limit |
Density: | 12.0 g/cm3 |
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Melting point: | 1551.85 °C / 1825 °K |
Boiling point: | 3139.85 °C / 3413 °K |
Molar volume: | 8.85 cm3 |
Thermal conductivity: | 71.8 [300 K] Wm-1K-1 |
Coefficient of linear thermal expansion: | 11.2 x 10-6 K-1 |
Electrical resistivity: | 10.8x 10-8 [293 K] Wm |
Mass magnetic susceptibility: | +6.702 x 10-8(s) kg-1m3 |
Young's modulus: | 121 GPa |
Rigidity modulus: | 43.6 GPa |
Bulk modulus: | 187 GPa |
Poisson's ratio: | 0.39 GPa |
Radii: | Pd4+ 64; Pd2+ 86; atomic 138; covalent 128 |
Electronegativity: | 2.20 (Pauling); 1.35 (Allred); 4.45 eV (absolute) |
Effective nuclear charge: | 4.05 (Slater); 7.84 (Clementi); 11.11 (Froese-Fischer) |
Number of Isotopes (incl. nuclear isomers): | 25 |
Issotope mass range: | 96 -> 116 |
Crystal structure, (cell dimentions / pm), space group | fcc |
X-ray diffraction: mass absorption coefficients: | CuKα 206 (µ/r) / cm2g-1 MoKα 24.1 (µ/r) / cm2g-1 |
Neutron scattering length: | 0.591 b/10-12 cm |
Thermal neutron capture cross-section: | 6.9 sa / barns |
Biological role: | none |
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Toxicity | |
Toxic intake: | n.a. |
Lethal intake: | LD50 (chloride, oral, rat)25 = mg kg-1 |
Hazards: | Palladium is poorly absorbed by the body when ingested and PdCl2 was formerly presribed as a treatment for tuberculosis at the rate of 65 mg per day (approximately 1 mg kg-1 without apparent ill effec |
Level in humans | |
Blood: | |
Bone: | |
Liver: | |
Muscle: | |
Daily dietary intake: | n.a. |
Total mass of element in average [70 kg] person: | n.a. |
Mineral | Formula | Density | Hardness | Crystal apperance |
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Palladium | Pd | 11.9 | 4.5 - 5 | cub. met. white/grey |
Chief ore: | speciments of the native metal are found in Brazil. Most is extracted as a by-product from copper an |
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World production: | 24 tonnes/year |
Main mining areas: | see copper and zinc |
Reserves: | 24 000 tonnes |
Specimen: | available as foil, granules, powder, rod, shot sponge or wire. Safe. |
Abundances | |
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Sun: | 32 (relative to H = 1 x 1012) |
Earth's crust: | c. 6 x 10-4 p.p.m. |
Seawater: | |
Residence time: | |
Classification: | recycled |
Oxidation state: | II |