Bismuth(III) Oxide
Bismuth(III) oxide, also known as bismuth trioxide or bismuth sesquioxide, is a chemical compound with the formula Bi2O3. It is a yellowish-brown or reddish-gray powder that is insoluble in water but soluble in acids.
Bismuth(III) oxide has a rhombohedral crystal structure and exhibits semiconducting properties. It is used in the manufacture of ceramics, glass, and pigments. It is also used as a catalyst in organic synthesis and as a flame retardant in plastics.
In its pure form, bismuth(III) oxide is not considered toxic, although it may release toxic fumes when heated or exposed to acid. However, it may contain impurities such as lead and arsenic, which can be harmful if ingested or inhaled.
Bismuth(III) oxide can be prepared by heating bismuth metal in air, or by thermal decomposition of bismuth nitrate or bismuth carbonate. It is also commercially available from chemical suppliers.
In summary, bismuth(III) oxide is a yellowish-brown or reddish-gray powder that has semiconducting properties and is used in the manufacture of ceramics, glass, and pigments. It can be prepared by heating bismuth metal in air, and may contain impurities that can be harmful if ingested or inhaled.