Tungsten
. Tungsten, symbol W (from the earlier name, wolfram), metallic element that has the highest melting point of any metal. Tungsten is one of the transition elements of the periodic table . The atomic number of tungsten is 74. Some credit the Swedish chemist Carl Wilhelm Scheele with the discovery of tungsten in 1781, while others name the Spanish D'Elhuyar brothers Juan José and Fausto as its discoverers, in 1783. Pure tungsten is silver-white in color and is ductile; the more easily obtained impure form is steel-gray and is hard and brittle. Tungsten is insoluble in hot and cold water and in alcohol, slightly soluble in ammonia and nitric acid, and soluble in hot, concentrated potassium hydroxide. Tungsten melts at about 3420°C (6190°F), boils at about 5660°C (10,220°F), and has a specific gravity of 19.5. The atomic weight of tungsten is 183.85. Tungsten ranks 57th in abundance among the elements in the crust of the earth. It is never found free in nature, but occurs in combinat...