kromioksidi

Kromioksidi, known in English as chromium oxide, refers to inorganic oxide compounds containing chromium and oxygen. The most common forms are chromium(III) oxide Cr2O3 (chromia) and chromium(VI) oxide CrO3 (chromyl oxide). The natural mineral eskolaite is Cr2O3.

Chromium(III) oxide Cr2O3 is a stable, green solid that is largely insoluble in water and resistant to many acids. It is widely used as a green pigment, known as chromium oxide green, in paints, ceramics, and glass. It also serves as a fine abrasive for polishing and as a component in some protective coatings and refractory materials. Commercial Cr2O3 is typically produced by calcining chromium(III) hydroxide or related hydrated oxides.

Chromium(VI) oxide CrO3 is a highly oxidizing, orange-red crystalline solid. It dissolves in water to form chromic acid and related species. CrO3 is used industrially as an oxidizer in chemical synthesis, as a precursor to various chromium salts, and in some chrome-plating processes. Because chromium in the +6 oxidation state is toxic and carcinogenic, handling CrO3 requires strict safety measures and appropriate controls to limit exposure.

Safety and regulation: Cr(VI) compounds are tightly regulated due to their health hazards, including carcinogenicity. Cr(III) compounds like Cr2O3 are less soluble and generally pose lower acute risks, though exposure should still be minimized. Proper containment, ventilation, and personal protective equipment are recommended when working with chromium oxides.

See also: chromium, chromium(III) oxide, chromium(VI) compounds, pigments.