The use of Siberian red lead as a paint pigment developed rapidly. In 1770, Peter Simon Pallas visited the same site as Lehmann and found a red "lead" mineral that had very useful properties as a pigment in paints. Though misidentified as a lead compound with selenium and iron components, the material was in fact lead chromate with a formula of PbCrO 4, now known as the mineral crocoite. In 1761, Johann Gottlob Lehmann found an orange-red mineral in the Ural Mountains which he named Siberian red lead. In medicine, as a dietary supplement or slimming aid, usually as chromium (III) chloride or chromium(III) picolinate.In well drilling muds as an anti-corrosive.Chromium(IV) oxide (CrO 2) is used to manufacture magnetic tape, where its higher coercivity than iron oxide tapes gives better performance.It is also used as a mordant (i.e., a fixing agent) for dyes in fabric. Potassium dichromate is a chemical reagent, used in cleaning laboratory glassware and as a titrating agent.Chromium salts are used in the tanning of leather.Chromite is used to make molds for the firing of bricks.also makes a brilliant yellow for painting.
Chromium is what makes a ruby red, and therefore is used in producing synthetic rubies.Chromium salts colour glass an emerald green.Chromium(III) oxide is a metal polish known as green rouge.in anodized aluminium, literally turning the surface of aluminium into ruby.as an alloy constituent, such as in stainless steel in cutlery.In metallurgy, to impart corrosion resistance and a shiny finish :.forms a very thin, insoluble, protective oxide which prevents further oxidation of the underlying metal.
Chromium compounds of oxidation state 6 are powerful oxidants.Ĭhromium is passive with oxygen, i.e. The most common oxidation states of chromium are +2, +3, and +6, with +3 being the most stable. It is also odourless, tasteless, and is somewhat malleable. Chromium ( IPA: /ˈkrəʊmiəm/) is a chemical element in the periodic table that has the symbol Cr and atomic number 24.Ĭhromium is a steel-gray, lustrous, hard metal that takes a high polish, and has a high melting point.
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