Arsenous oxide

Arsenous oxide, also known as arsenic trioxide or white arsenic, is an inorganic compound with the formula As2O3. This white crystalline solid is well known as a poison, but also has various other applications.

Chemical properties

Arsenous oxide is an amphoteric oxide, and its aqueous solutions are weakly acidic. It reacts with alkalis to yield arsenites. It can be readily oxidized to arsenic pentoxide and reduced to elemental arsenic by heating with carbon.

Production

Arsenous oxide is obtained as a byproduct from the roasting of arsenic-containing ores of copper and lead. It can also be prepared by the reduction of arsenic acid with hydrogen.

Applications

Despite its toxicity, arsenous oxide has found use in a variety of applications. It is used in the glass industry to remove greenish tint caused by iron impurities. In medicine, it is used as a chemotherapeutic agent for the treatment of acute promyelocytic leukemia.

Toxicity

Arsenous oxide is highly toxic and carcinogenic. It is readily absorbed by the gastrointestinal tract, and can also be inhaled as dust or fume. Chronic exposure can lead to arsenic poisoning, which can cause a variety of symptoms including skin lesions, peripheral neuropathy, and gastrointestinal symptoms.

See also

• Arsenic
• Arsenic poisoning
• Acute promyelocytic leukemia