See more Chromium products. Chromium (atomic symbol: Cr, atomic number: 24) is a Block D, Group 6, Period 4 element with an atomic weight of 51.9961. The number of electrons in each of Chromium's shells is 2, 8, 13, 1 and its electron configuration is [Ar] 3d5 4s1. Chromium was first discovered by Louis Nicolas Vauquelin in 1797. It was first isolated in 1798, also by Louis Nicolas Vauquelin. The chromium atom has a radius of 128 pm and a Van der Waals radius of 189 pm. In its elemental form, chromium has a lustrous steel-gray appearance. Chromium is the hardest metal element in the periodic table and the only element that exhibits antiferromagnetic ordering at room temperature, above which it tranforms into a paramagnetic solid. The most common source of chromium is chromite ore (FeCr2O4). Due to its various colorful compounds, Chromium was named after the Greek word 'chroma' meaning color.
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 Nickel products. Nickel (atomic symbol: Ni, atomic number: 28) is a Block D, Group 4, Period 4 element with an atomic weight of 58.6934. The number of electrons in each of nickel's shells is [2, 8, 16, 2] and its electron configuration is [Ar]3d8 4s2. Nickel was first discovered by Alex Constedt in 1751. The nickel atom has a radius of 124 pm and a Van der Waals radius of 184 pm. In its elemental form, nickel has a lustrous metallic silver appearance. Nickel is a hard and ductile transition metal that is considered corrosion-resistant because of its slow rate of oxidation. It is one of four elements that are ferromagnetic and is used in the production of various type of magnets for commercial use. Nickel is sometimes found free in nature but is more commonly found in ores. The bulk of mined nickel comes from laterite and magmatic sulfide ores. The name originates from the German word kupfernickel, which means "false copper" from the illusory copper color of the ore.
See more Tungsten products. Tungsten (atomic symbol: W, atomic number: 74) is a Block D, Group 6, Period 6 element with an atomic weight of 183.84. The number of electrons in each of tungsten's shells is [2, 8, 18, 32, 12, 2] and its electron configuration is [Xe] 4f14 5d4 6s2. The tungsten atom has a radius of 139 pm and a Van der Waals radius of 210 pm. Tungsten was discovered by Torbern Bergman in 1781 and first isolated by Juan José Elhuyar and Fausto Elhuyar in 1783. In its elemental form, tungsten has a grayish white, lustrous appearance. Tungsten has the highest melting point of all the metallic elements and a density comparable to that or uranium or gold and about 1.7 times that of lead. Tungsten alloys are often used to make filaments and targets of x-ray tubes. It is found in the minerals scheelite (CaWO4) and wolframite [(Fe,Mn)WO4]. In reference to its density, Tungsten gets its name from the Swedish words tung and sten, meaning heavy stone.