Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Arsenic pentoxide

Arsenic pentoxide is a white amorphous powder.

CAS 1303-28-2 Danger

01 · Identification

What Arsenic pentoxide is

Arsenic pentoxide is a white amorphous powder. It boils at 160 °C, melts at 315 °C.

Under the GHS it carries the signal word Danger. It is classed as carcinogens.

CAS number1303-28-2
EC number215-116-9
Index number033-004-00-6
Chemical class Carcinogens

Other names for Arsenic pentoxide

  • diarsenic pentaoxide
  • arsenic oxide

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.

Signal wordDanger
Hazard statements assigned to Arsenic pentoxide
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H331 Toxic if inhaled.
H301 Toxic if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P201, P260, P270, P271, P273, P280, P301, P304, P308, P310, P313, P330, P391, P501

This page lists only the codes assigned to Arsenic pentoxide. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

03 · Physical and chemical properties

Arsenic pentoxide 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 160 °C (320 °F) Hemihydrate HSDB
Melting point 315 °C (599 °F) HSDB
Density 4.32 g/cm³ HSDB
4.3 g/cm³ ICSC
Solubility Freely soluble in water or alcohol HSDB
Very soluble in ethanol HSDB
In water, 65.8 g/100 g at 20 °C at 20 °C HSDB
Flash point Not flammable (EPA, 1998) CAMEO
Lower explosive limit (LEL) Containers may explode when heated 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 pentoxide

Storage conditions

Store in tightly-closed containers in a cool, well-ventilated area away from metals, acids and other incompatible materials.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

With bromine pentafluoride: Contact with arsenic pentoxide at ambient or slightly elevated temperatures is violent, ignition often occurring.

Source: Hazardous Substances Data Bank (HSDB)

Planning storage for a mix of chemicals? Check Arsenic pentoxide in the storage compatibility matrix →

Safety Data Sheet

Getting an SDS for Arsenic pentoxide

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Arsenic pentoxide issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

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Substances next to Arsenic pentoxide

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