Gadolinium (Gd)

Science / Periodic Table of Elements / Gadolinium (Gd): Atomic number: 64, Atomic mass: 157.25 g.mol -1, Electronegativity: 1.1, Density: 7.9 at 20°C, Melting point: 1313 °C, Boiling point: 3266 °C, Vanderwaals radius: unknown, Ionic radius: unknown, Isotopes: 13, Electronic shell: [ Xe ] 4f7 5d1 6s2, Energy of first ionisation: 591.4 kJ.mol -1, Energy of second ionisation: 1165.5 kJ.mol -1, Standard potential: - 2.40 V, Discovered by: Jean de Marignac in 1880. Gadolinium is a soft, shiny, ductile, silvery metal belonging to the lanthanide group of the periodic chart. The metal does not tarnish in dry air but an oxide film forms in moist air. Gadolinium reacts slowly with water and dissolves in acids. Gadolinium becomes superconductive below 1083 K. It is strongly magnetic at room temperature. Applications: Gadolinium has found some use in control rods for nuclear reactors and nuclear power plants; it is used to make garnets for microwave applications and its compounds are used for making phosphorous for colour TV tubes. Metallic gadolinium is rarely used as the metal itself, but its alloys are used to make magnets and electronic components such as recording heads for video recorders. It is also used for manufacturing compact disks and computer memory. Gadolinium in the environment: Gadolinium is one of the more abundant rare-earth elements. It is never found as free element in nature, but it is contained in many rare minerals. The main mining areas are Cina, USA, Brazil, Sri Lanka, India and Australia with reserves expected to exceed one million tonnes. World production of pure gadolinium is about 400 tonnes per year