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History and Production
From Latin Scandia, Scandinavia. The element in oxide form was discovered by L.F. Nilsen in 1878 in minerals euxenite and gadolinite. These are rare minerals found only in Scandinavia. P.T. Cleve later pointed out that the properties of the new element was
identical to the D.I. Mendeleev prediction of yet undiscovered element ekaboron. It was only in 1937 that the metal itself was isolated by the electrolysis of molten chlorides of potassium, lithium and scandium and pure (99%) scandium was started to produce only in 1960. Scandium nowadays can be recovered from thortveitite mineral (Sc2Si2O7),
or as a byproduct in the processing of uranium ores. Purer form of metal can be produced from
the reduction of calcium with scandium fluoride. The metal has little commercial and technological use and hence large-scale production has not been realized. However, the isotope 46Sc has been used as a tracing agent in oil refinery work.
Physical Data
It is a silver-white metal which appears slightly yellowish or pinkish when exposes to air. It is very light with very high melting point. It was once thought that the metal is rare but in fact the abundance (25 ppm) is comparable to that of cobalt (29 ppm).
Scandium can be found in thortveitite, Sc2Si2O7, a rare mineral from Norway.
Interatomic distance: 321.2 pm
Melting point: 1541°C
Boiling point: 2836°C
Thermal conductivity/Wm-1K-1: 15.8 (27°C)
Density/kgm-3: 2989 (0°C)
Standard Thermodynamic Data (atomic gas)
Enthalpy of formation: 377.8 kJ/mol
Gibbs free energy of formation: 336 kJ/mol
Entropy: 174.8 J/mol K
Heat capacity: 22.1 J/mol K
Electronic data
Electronic configuration: [Ar] 3d1 4s2
Term symbol: 2D3/2
Electron affinity: 18.1393 kJ/mol Electronegativity (Pauline): 1.36
Ionization energy (first, second, third): 633.089, 1234.98, 2388.66 kJ/mol
Chemical properties
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