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

Pentachloronaphthalene

Pentachloronaphthalene is a white powder with an aromatic odor.

CAS 1321-64-8 C10H3Cl5 300.4 g/mol Warning

01 · Identification

What Pentachloronaphthalene is

Pentachloronaphthalene is a white powder with an aromatic odor. Its molecular formula is C10H3Cl5 and its molecular weight is 300.4 g/mol. It boils at 250 °C, melts at 120 °C.

Under the GHS it carries the signal word Warning.

CAS number1321-64-8
EC number215-320-8
Index number602-041-00-5
Molecular formulaC10H3Cl5
Molecular weight300.4 g/mol

Other names for Pentachloronaphthalene

  • penthachloronaphthalene

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 wordWarning
Hazard statements assigned to Pentachloronaphthalene
CodeHazard statement
H312 Harmful in contact with skin.
H302 Harmful if swallowed.
H315 Causes skin irritation.
H319 Causes serious eye irritation.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P264, P270, P273, P280, P301, P302, P305, P312, P313, P330, P332, P337, P338, P352, P391, P501

03 · Physical and chemical properties

Pentachloronaphthalene 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 250 °C (482 °F) initial boiling point HSDB
335.56 °C (636 °F) NIOSH
335.56 °C (636 °F) at 760 mmHg CAMEO
Melting point 120 °C (248 °F) HSDB
Density 1.67 g/cm³ NIOSH
1.67 g/cm³ at 25 °C HSDB
Solubility ... Soluble in organic solvents. HSDB
Insoluble NIOSH
Vapor pressure 1 mmHg below this value NIOSH
1 mmHg below this value, at 20 °C HSDB
Flash point 230 °C (446 °F) OPEN CUP HSDB
Lower explosive limit (LEL) Noncombustible Solid NIOSH
Vapor density 10.4 (air = 1) ICSC

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

04 · Source notes

Further notes on Pentachloronaphthalene

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

POLYCHLORONAPHTHALENES HAVE GOOD SOLUBILITY IN CHLORINATED & AROMATIC SOLVENTS, & PETROLEUM NAPHTHAS; LIMITED IN KETONES, ETHERS, ACETATES, MINERAL OILS; INSOL IN ALC, WATER. /POLYCHLORONAPHTHALENES/

Source: HSDB

05 · Handling and storage

Storing and handling Pentachloronaphthalene

Storage conditions

Materials which are toxic as stored or which decompose into toxic components due to contact with heat ... should be stored in cool, well-ventilated place, out of direct rays of sun, away from areas of high fire hazard, and ... periodically inspected and monitored.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizers.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

PENTACHLORONAPHTHALENE is non-flammable, but combustible. Gives off irritating or toxic gases in a fire. Incompatible with strong oxidizing agents. Reacts violently with aluminum, with bases, and with liquid O2.

Source: CAMEO Chemicals

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

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