Tungsten is a rare high melting point metal, belonging to the family of VIB of the periodic table of the sixth cycle (second cycle). Tungsten is a silver-white metal appearance similar to steel. Tungsten's high melting point, low vapor pressure, the evaporation rate is also small. The chemical properties of tungsten is very stable at room temperature without reaction with air and water, not heated, any concentration of hydrochloric acid, sulfuric acid, nitric acid, hydrofluoric acid and aqua regia tungsten does not work, when the temperature rose to 80 ° -100 ° C, the above-mentioned acid addition to hydrofluoric acid, other acids of tungsten weak role. Room temperature, the tungsten can be quickly dissolved in the mixed acid of hydrofluoric acid and concentrated nitric acid, but does not work in the alkali solution. Air conditions, the molten alkali tungsten oxide into the tungstate in the presence of oxidants (NaNO3, NaNO2, potassium chlorate, PbO2 by) generated tungstate reaction is more violent. High temperature with chlorine, bromine, iodine, carbon, nitrogen, sulfur compounds, but not together with the hydride.
Tungsten directory site combines all the weights of the website on tungsten.
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