An Overview of Scandium (Sc or Element 21)

An Overview of Scandium (Sc or Element 21) Basic Facts Atomic Number: 21Symbol: ScAtomic Weight: 44.95591Discovery: Lars Nilson 1878 (Sweden)Electron Configuration: [Ar] 4s2 3d1Word Origin: Latin Scandia: ScandinaviaIsotopes: Scandium has 24 known isotopes ranging from Sc-38 to Sc-61. Sc-45 is the only stable isotope.Properties: Scandium has a melting point of 1541 Â °C, a boiling point of 2830 Â °C, a specific gravity of 2.989 (25 Â °C), and valence of 3. It is a silvery-white metal which develops a yellowish or pinkish cast when exposed to air. Scandium is a very light, relatively soft metal. Scandium reacts rapidly with many acids. The blue color of aquamarine is attributed to the presence of scandium.Sources: Scandium is found in the minerals thortveitite, euxenite, and gadolinite. It is also produced as a byproduct of uranium refinement.Uses: Scandium is used to make high-intensity lamps. Scandium iodide is added to mercury vapor lamps to produce a light source with a color resembling sunlight. The radioactive isotope Sc-46 is us ed as a tracer in refinery crackers for crude oil. Element Classification: Transition Metal Physical Data Density (g/cc): 2.99Melting Point (K): 1814Boiling Point (K): 3104Appearance: somewhat soft, silvery-white metalAtomic Radius (pm): 162Atomic Volume (cc/mol): 15.0Covalent Radius (pm): 144Ionic Radius: 72.3 (3e)Specific Heat (20Â °C J/g mol): 0.556Fusion Heat (kJ/mol): 15.8Evaporation Heat (kJ/mol): 332.7Pauling Negativity Number: 1.36First Ionizing Energy (kJ/mol): 630.8Oxidation States: 3Standard Reduction Potential: Sc3 e → Sc E0 -2.077 VLattice Structure: HexagonalLattice Constant (Ã…): 3.310Lattice C/A Ratio: 1.594CAS Registry Number: 7440-20-2 Trivia Scandium was named after Scandinavia. Chemist Lars Nilson was attempting to isolate the element ytterbium from the minerals euxenite and gadolinite when he discovered scandium. These minerals were primarily found in the Scandinavia region.Scandium is the transition metal with the lowest atomic number.The discovery of scandium filled a spot predicted by Mendeleevs periodic table. Scandium took the place of the placeholder element eka-boron.Most scandium compounds have scandium with the Sc3 ion.Scandium has an abundance in the Earths crust of 22 mg/kg (or parts per million).Scandium has an abundance in seawater of 6 x 10-7 mg/L (or parts per million).Scandium is more abundant on the Moon than on Earth. References: Los Alamos National Laboratory (2001) Crescent Chemical Company (2001)Langes Handbook of Chemistry (1952)CRC Handbook of Chemistry Physics (18th Ed.) International Atomic Energy Agency ENSDF database (Oct 2010)