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

Hexachlorobenzene

Hexachlorobenzene is white needles.

CAS 118-74-1 C6Cl6 284.8 g/mol Danger

01 · Identification

What Hexachlorobenzene is

Hexachlorobenzene is white needles. Its molecular formula is C6Cl6 and its molecular weight is 284.8 g/mol. It boils at 325 °C, melts at 229 °C.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number118-74-1
EC number204-273-9
Index number602-065-00-6
Molecular formulaC6Cl6
Molecular weight284.8 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

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 Hexachlorobenzene
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H372 Causes damage to organs <or state all organs affected, if known> through prolonged or repeated exposure <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P201, P260, P270, P273, P280, P308, P313, P314, P391, P501

03 · Physical and chemical properties

Hexachlorobenzene 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 325 °C (617 °F) HSDB
322.22 °C (612 °F) OSHA
325 °C (617 °F) at 760 mmHg DOE PAC
Melting point 228.83 °C (443.9 °F) HSDB
200 °C (392 °F) Technical product HSDB
231 °C (447.8 °F) ICSC
Density 2 g/cm³ ICSC
2.044 g/cm³ at 23 °C HSDB
2.044 g/cm³ at 24 °C CAMEO
Solubility Sparingly soluble in cold alcohol; soluble in benzene, chloroform, and ether HSDB
Soluble in carbon disulfide; sparingly soluble in carbon tetrachloride HSDB
In water, 4.7X10-3 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 0.000007501 mmHg at 20 °C ICSC
0.0000172 mmHg at 25 °C HSDB
1 mmHg at 114.39 °C CAMEO
Flash point 242 °C (467.6 °F) closed cup HSDB
242.22 °C (468 °F) CAMEO
242 °C (467.6 °F) ICSC
Vapor density 9.83 (air = 1) HSDB
9.8 (air = 1) CAMEO

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

04 · Handling and storage

Storing and handling Hexachlorobenzene

Storage conditions

Separated from food and feedstuffs. Well closed.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

DIMETHYL FORMAMIDE AND HEXACHLOROBENZENE REACT VIOLENTLY ABOVE 65 °C.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

HEXACHLOROBENZENE reacts violently with dimethylformamide. (NTP, 1992).

Source: CAMEO Chemicals

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

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