Scandium is a silvery-white metal which develops a slightly yellowish or pinkish cast upon exposure to air. It is relatively soft, and resembles yttrium and the rare-earth metals more than it resembles aluminium or titanium. Scandium reacts rapidly with many acids.
Scandium is apparently a much more abundant element in the sun and certain stars than on earth.
Image adapted with permission fromProf James Marshall Prof James Marshall's (U. North Texas, USA)Walking Tour of the elements CD.
Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of scandium where known.
Isolation: preparation of metallic samples of scandium is not normally necessary given that it is commercially avaialable. In practice littel scandium is produced. The mineral thortveitite contains 35-40% Sc2O3 is used to produce scandium metal but another important source is as a byproduct from uranium ore processing, even though these only contain 0.02% Sc2O3.
Density of solid: 2985 kg m-3
Molar volume: 15.00 cm3
Thermal conductivity: 16 W m‑1 K‑1
Melting point: 1814 [1541 °C (2806 °F)] K
Boiling point: 3103 [2830 °C (5126 °F)] K
Enthalpy of fusion: 20.5 kJ mol-1
Atomic radius (empirical): 160 pm
Molecular single bond covalent radius: 148 (coordination number 3) ppm
van der Waals radius: 258 ppm
Pauling electronegativity: 1.36 (Pauling units)
Allred Rochow electronegativity: 1.20 (Pauling units)
Mulliken-Jaffe electronegativity: (no data)
First ionisation energy: 633.09 kJ mol‑1
Second ionisation energy: 1234.99 kJ mol‑1
Third ionisation energy: 2388.67 kJ mol‑1
Universe: 30 ppb by weight
Crustal rocks: 26000 ppb by weight
Human: (no data) ppb by weight
