See more Cerium products. Cerium (atomic symbol: Ce, atomic number: 58) is a Block F, Group 3, Period 6 element with an atomic weight of 140.116. The number of electrons in each of cerium's shells is 2, 8, 18, 19, 9, 2 and its electron configuration is [Xe]4f2 6s2. The cerium atom has a radius of 182.5 pm and a Van der Waals radius of 235 pm. In its elemental form, cerium has a silvery white appearance. Cerium is the most abundant of the rare earth metals. It is characterized chemically by having two valence states, the +3 cerous and +4 ceric states. The ceric state is the only non-trivalent rare earth ion stable in aqueous solutions. It is, therefore, strongly acidic and moderately toxic. It is also a strong oxidizer. The cerous state closely resembles the other trivalent rare earths. Cerium is found in the minerals allanite, bastnasite, hydroxylbastnasite, monazite, rhabdophane, synchysite and zircon. Cerium was discovered by Martin Heinrich Klaproth, Jöns Jakob Berzelius, and Wilh elm Hisinger in 1803 and first isolated by Carl Gustaf Mosander in 1839. The element was named after the asteroid Ceres.
See more Cobalt products. Cobalt (atomic symbol: Co, atomic number: 27) is a Block D, Group 9, Period 4 element with an atomic weight of 58.933195. The number of electrons in each of cobalt's shells is 2, 8, 15, 2 and its electron configuration is [Ar] 3d7 4s2The cobalt atom has a radius of 125 pm and a Van der Waals radius of 192 pm. Cobalt was first discovered by George Brandt in 1732. In its elemental form, cobalt has a lustrous gray appearance. Cobalt is found in cobaltite, erythrite, glaucodot and skutterudite ores. Cobalt produces brilliant blue pigments which have been used since ancient times to color paint and glass. Cobalt is a ferromagnetic metal and is used primarily in the production of magnetic and high-strength superalloys. Co-60, a commercially important radioisotope, is useful as a radioactive tracer and gamma ray source. The origin of the word Cobalt comes from the German word "Kobalt" or "Kobold," which translates as "goblin," "elf" or "evil spirit." For more information on cobalt, including properties, safety data, research, and American Elements' catalog of cobalt products, visit the Cobalt element page.
See more Gadolinium products. Gadolinium (atomic symbol: Gd, atomic number: 64) is a Block F, Group 3, Period 6 element with an atomic radius of 157.25. The number of electrons in each of Gadolinium's shells is [2, 8, 18, 25, 9, 2] and its electron configuration is [Xe] 4f7 5d1 6s2. The gadolinium atom has a radius of 180 pm and a Van der Waals radius of 237 pm. Gadolinium was discovered by Jean Charles Galissard de Marignac in 1880 and first isolated by Lecoq de Boisbaudran in 1886. In its elemental form, gadolinium has a silvery-white appearance. Gadolinium is a rare earth or lanthanide element that possesses unique properties advantageous to specialized applications such as semiconductor fabrication and nuclear reactor shielding. It is utilized for both its high magnetic moment (7.94μ B) and in phosphors and scintillator crystals. When complexed with EDTA ligands, it is used as an injectable contrast agent for MRIs. The element is named after the Finnish chemist and geologist Johan Gadolin.
See more Iron products. Iron (atomic symbol: Fe, atomic number: 26) is a Block D, Group 8, Period 4 element with an atomic weight of 55.845. The number of electrons in each of Iron's shells is 2, 8, 14, 2 and its electron configuration is [Ar] 3d6 4s2. The iron atom has a radius of 126 pm and a Van der Waals radius of 194 pm. Iron was discovered by humans before 5000 BC. In its elemental form, iron has a lustrous grayish metallic appearance. Iron is the fourth most common element in the Earth's crust and the most common element by mass forming the earth as a whole. Iron is rarely found as a free element, since it tends to oxidize easily; it is usually found in minerals such as magnetite, hematite, goethite, limonite, or siderite. Though pure iron is typically soft, the addition of carbon creates the alloy known as steel, which is significantly stronger.
See more Strontium products. Strontium (atomic symbol: Sr, atomic number: 38) is a Block S, Group 2, Period 5 element with an atomic weight of 87.62 . The number of electrons in each of Strontium's shells is [2, 8, 18, 8, 2] and its electron configuration is [Kr] 5s2. The strontium atom has a radius of 215 pm and a Van der Waals radius of 249 pm. Strontium was discovered by William Cruickshank in 1787 and first isolated by Humphry Davy in 1808. In its elemental form, strontium is a soft, silvery white metallic solid that quickly turns yellow when exposed to air. Cathode ray tubes in televisions are made of strontium, which are becoming increasingly displaced by other display technologies pyrotechnics and fireworks employ strontium salts to achieve a bright red color. Radioactive isotopes of strontium have been used in radioisotope thermoelectric generators (RTGs) and for certain cancer treatments. In nature, most strontium is found in celestite (as strontium sulfate) and strontianite (as strontium carbonate). Strontium was named after the Scottish town where it was discovered.