Tungsten Tungsten Tungsten, or wolfram, is a chemical element with symbol W and atomic number 74. The name "tungsten" comes from the former Swedish name for the tungstate mineral "scheelite", "tung sten" or "heavy stone". Tungsten is a rare metal found naturally on Earth almost exclusively combined with other elements in chemical compounds rather than alone. It was identified as a new element in 1781 and first isolated as a metal in 1783. Its important ores include wolframite and scheelite. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all the
Melting-point apparatus Melting-point apparatus A melting-point apparatus is a scientific instrument used to determine the melting point of a substance. Some types of melting-point apparatuses include the Thiele tube, Fisher-Johns apparatus, Gallenkamp (Electronic) melting-point apparatus and automatic melting-point apparatus. While the outward designs of apparatuses can vary greatly, most apparatuses use a sample loaded into a sealed capillary ("melting-point capillary"), which is then placed in the apparatus. The sample is then heated, either by a heating block or an oil bath, and as the temperature increases, the sample is observed to determine when the phase change from solid to liquid occurs. The