Tungsten

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Tungsten, chemical symbol W, is a heavy metal which got it's name from the Swedish words "Tung sten" which means heavy stone. Funny enough, in Sweden Tungsten is called volfram from the German "wolf rahm". Tungsten is used in many technical areas, one that gold refiners sometime come in contact with, for example on the heat spreader made of a copper tungsten alloy. It is highly resistant against most acids, including aqua regia, and only slowly attacked.

Chemistry

Tungsten can be dissolved in hydrogen peroxide (H2O2) forming WO3.H2O2.
Adding sulfuric acid to a solution containing WO3.H2O2 precipitates tungstic acid as a yellow powder.

References

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