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

Isobenzan

Isobenzan is a whitish to light brown powder.

CAS 297-78-9 C9H4Cl8O 411.7 g/mol Danger

01 · Identification

What Isobenzan is

Isobenzan is a whitish to light brown powder. Its molecular formula is C9H4Cl8O and its molecular weight is 411.7 g/mol. It melts at 121 °C.

Under the GHS it carries the signal word Danger.

CAS number297-78-9
EC number206-045-4
Index number602-053-00-0
Molecular formulaC9H4Cl8O
Molecular weight411.7 g/mol

Other names for Isobenzan

  • isobenzan (ISO)
  • 1,3,4,5,6,7,8,8-octachloro-1,3,3a,4,7,7a-hexahydro-4,7-methanoisobenzofuran

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 Isobenzan
CodeHazard statement
H310 Fatal in contact with skin.
H300 Fatal if swallowed.
H400 Very toxic to aquatic life.

Precautionary statements: P270, P273, P280, P301, P302, P310, P330, P352, P391, P501

03 · Physical and chemical properties

Isobenzan 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
Melting point 121 °C (249.8 °F) range, midpoint shown HSDB
121.11 °C (250 °F) range, midpoint shown CAMEO
Density 1.87 g/cm³ HSDB
1.87 g/cm³ at 25 °C DOE PAC
Solubility Sol in ether, acetone, benzene, xylene, heavy aromatic naphtha HSDB
Greater than 1% in ethanol & kerosene HSDB
Vapor pressure 0.000003 mmHg at 20 °C HSDB
0.00000292 mmHg at 20 °C HSDB
0.00001 mmHg at 25 °C CAMEO
Lower explosive limit (LEL) Non-flammable and non-explosive. (EPA, 1998) CAMEO
Upper explosive limit (UEL) Non-flammable and non-explosive. (EPA, 1998) CAMEO

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

04 · Source notes

Further notes on Isobenzan

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

25 g/100 ml acetone at 25 °C, 38 g/100 ml benzene at 25 °C, 34 g/100 ml carbon tetrachloride at 25 °C, 2 g/100 ml fuel oil at 25 °C, 34 g/100 ml toluene at 25 °C, 29 g/100 ml xylene at 25 °C.

Source: HSDB

05 · Handling and storage

Storing and handling Isobenzan

Reactivity

Chlorine is evolved when ISOBENZAN is heated above 410F. Avoid acids, certain metal salts, and catalytically active carriers. [EPA, 1998].

Source: CAMEO Chemicals

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

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