Substance profile
Arsenic Trioxide
Arsenic Trioxide is white cubic crystals (Arsenolite) and is odorless.
01 · Identification
What Arsenic Trioxide is
Arsenic Trioxide is white cubic crystals (Arsenolite) and is odorless. It boils at 460 °C, melts at 313 °C, is soluble in water.
Under the GHS it carries the signal word Danger. It is classed as carcinogens.
Other names for Arsenic Trioxide
- diarsenic trioxide
02 · GHS classification
Hazards and label elements
Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.
| Code | Hazard statement |
|---|---|
| H350 | May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. |
| H300 | Fatal if swallowed. |
| H314 | Causes severe skin burns and eye damage. |
| H400 | Very toxic to aquatic life. |
| H410 | Very toxic to aquatic life with long lasting effects. |
Precautionary statements: P201, P260, P270, P273, P280, P301, P308, P310, P313, P330, P331, P391, P501
03 · Physical and chemical properties
Arsenic Trioxide properties
Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.
| Property | Value | Conditions | Source |
|---|---|---|---|
| Boiling point | 460 °C (860 °F) | HSDB | |
| 465 °C (869 °F) | at 760 mmHg | CAMEO | |
| Melting point | 313 °C (595.4 °F) | claudetite | HSDB |
| 274 °C (525.2 °F) | DOE PAC | ||
| 252.53 °C (486.6 °F) | range, midpoint shown | CAMEO | |
| Density | 3.865 g/cm³ | cubes | HSDB |
| 3.738 g/cm³ | CAMEO | ||
| 3.86 g/cm³ | at 25 °C | DOE PAC | |
| Solubility | SOL IN DIL HYDROCHLORIC ACID, IN ALKALI HYDROXIDE; SOL IN CARBONATE SOLN; PRACTICALLY INSOL IN ALC; PRACTICALLY INSOL IN CHLOROFORM, ETHER. | HSDB | |
| Soluble in glycerol | HSDB | ||
| Solubility in water, g/100ml at 20 °C: 1.2-3.7 | at 20 °C | ICSC | |
| Vapor pressure | 0.000247 mmHg | at 25 °C | HSDB |
| 66.1 mmHg | at 312 °C | CAMEO | |
| 0.000247 mmHg | Haz-Map | ||
| Lower explosive limit (LEL) | Not flammable | HSDB | |
| Not flammable. (EPA, 1998) | CAMEO | ||
| Upper explosive limit (UEL) | Not flammable. (EPA, 1998) | CAMEO | |
| Critical temperature and pressure | 927 °C (1700.6 °F) | HSDB | |
| Corrosivity | Corrosive to metals in the presence of moisture. | HSDB |
Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.
04 · Handling and storage
Storing and handling Arsenic Trioxide
Storage conditions
Store in a cool, dry, well-ventilated location. Separate from acids, halogens, and iron salts.
Source: Hazardous Substances Data Bank (HSDB)
Incompatible materials
A mixture of arsenic trioxide with excess zinc filings will explode on heating.
Source: Hazardous Substances Data Bank (HSDB)
Reactivity
ARSENIC TRIOXIDE reacts vigorously with fluorine at ordinary temperatures [Mellor 9:34 1946-47]. Dissolves in aqueous acids. Incompatible with tannic acid, infusions of cinchona and other vegetable astringent infusions and decoctions, and with iron in solution [Merck].
Source: CAMEO Chemicals
Planning storage for a mix of chemicals? Check Arsenic Trioxide in the storage compatibility matrix →