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

Tetraphosphorus trisulphide

Tetraphosphorus trisulphide is yellow-green orthogonal crystals.

CAS 1314-85-8 P4S3 220.1 g/mol Danger

01 · Identification

What Tetraphosphorus trisulphide is

Tetraphosphorus trisulphide is yellow-green orthogonal crystals. Its molecular formula is P4S3 and its molecular weight is 220.1 g/mol. It boils at 408 °C, melts at 173 °C.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 2nd degree.

CAS number1314-85-8
EC number215-245-0
Index number015-012-00-1
Molecular formulaP4S3
Molecular weight220.1 g/mol
Chemical class Flammable agents - 2nd degree

Other names for Tetraphosphorus trisulphide

  • phosphorus sesquisulphid

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 Tetraphosphorus trisulphide
CodeHazard statement
H228 Flammable solid.
H260 In contact with water releases flammable gases which may ignite spontaneously.
H302 Harmful if swallowed.
H400 Very toxic to aquatic life.

Precautionary statements: P270, P273, P301, P312, P330, P391, P501

03 · Physical and chemical properties

Tetraphosphorus trisulphide 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 407.5 °C (765.5 °F) HSDB
Melting point 172.5 °C (342.5 °F) HSDB
Density 2.03 g/cm³ at 20 °C HSDB
Solubility Solubility in benzene = 2.5 g/100g at 17 °C, 17 g/100g at 80 °C at 17 °C HSDB
100 G/100 CC CARBON DISULFIDE AT 17 °C; 11.1 G/100 CC BENZENE AT 30 °C at 17 °C HSDB
Autoignition temperature 100 °C (212 °F) HSDB
Lower explosive limit (LEL) Flammable by spontaneous ignition. HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Source notes

Further notes on Tetraphosphorus trisulphide

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Solubility

Insoluble in cold water; decomposed by hot water, yielding H2S; Soluble in carbon disulfide (60% w/w at 20 °C); soluble in benzene, similar hydrocarbons, phorphorus trichloride

Source: HSDB

05 · Handling and storage

Storing and handling Tetraphosphorus trisulphide

Storage conditions

Protect against physical damage. Store in cool, ventilated place. Separate from other materials.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Decomp by hot water, yielding hydrogen sulfide (H2S)

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

PHOSPHORUS SESQUISULFIDE is a reducing agent.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Tetraphosphorus trisulphi… in the storage compatibility matrix →

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