Arsenious Oxide is also called Arsenic Trioxide.
Preparation of Arsenious Oxide
Arsenic trioxide is formed when arsenic is heated in air.
4As + 3O2 → 2As2O3
On an industrial scale, it is produced by air-roasting arsenic pyrite.
2FeAsS + 5O2 → As2O3 + Fe2O3 + 2SO2
Arsenious Oxide Physical Properties
It is a white colored toxic solid substance. It is found in amorphous and crystal forms. In crystal form, its crystals are of rhombic and octahedral form.
Arsenious Oxide Chemical Properties
Reaction with water
It dissolves in water to form arsenious acid.
As2O3 + 3H2O → 2H3AsO3
Reaction with concentrated HCl
It reacts with concentrated HCl to form arsenic chloride.
As2O3 + 6HCl → 3H2O + 2AsCl3
Reaction with NaOH
As2O3 + 6NaOH → 3H2O + 2Na3AsO3
Reaction with H2S
A yellow precipitate of arsenic sulfide is obtained when H2S gas is passed through a solution of As2O3.
As2O3 + 3H2S → 3H2O + As2S3
As2O3 + 2I2 + 2H2O → As2O5 + 4HI
As2O3 + 4HNO3 → As2O5 + 4NO2 + 2H2O
The As2O5 obtained in this reaction dissolves in water to form arsenic acid(H3AsO4).
As2O3 + 3H2O → 2H3AsO4
It is itself reduced to arsenic by reacting with reducing agents such as SnCl2 and carbon and oxidizes these substances.
As2O3 + 3SnCl2 + 6HCl → 2As + 3SnCl4 + 3H2O
As2O3 + 3C → 2As + 3CO
Arsenious Oxide Uses
It is used to kill rats and flies.
Used to make medicines.
It is used to keep animal skins safe.
It is used for making glass and paint.