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

1,2,4-Trichlorobenzene

1,2,4-Trichlorobenzene is a colorless liquid with an aromatic odor.

CAS 120-82-1 C6H3Cl3 181.4 g/mol Warning

01 · Identification

What 1,2,4-Trichlorobenzene is

1,2,4-Trichlorobenzene is a colorless liquid with an aromatic odor. Its molecular formula is C6H3Cl3 and its molecular weight is 181.4 g/mol. It boils at 214 °C, melts at 16.9 °C.

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

CAS number120-82-1
EC number204-428-0
Index number602-087-00-6
Molecular formulaC6H3Cl3
Molecular weight181.4 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 wordWarning
Hazard statements assigned to 1,2,4-Trichlorobenzene
CodeHazard statement
H302 Harmful if swallowed.
H315 Causes skin 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, P312, P313, P330, P332, P352, P391, P501

03 · Physical and chemical properties

1,2,4-Trichlorobenzene 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 213.5 °C (416.3 °F) HSDB
213.33 °C (416 °F) NIOSH
212.78 °C (415 °F) at 760 mmHg CAMEO
Melting point 16.92 °C (62.5 °F) HSDB
17.22 °C (63 °F) NIOSH
Density 1.4483 g/cm³ HSDB
0.447 g/cm³ HSDB
1.459 g/cm³ at 20 °C HSDB
Solubility Sparingly soluble in alcohol. Miscible with ether, benzene, petroleum ether, carbon disulfide HSDB
0.003% NIOSH
In water, 49.0 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 1 mmHg NIOSH
0.46 mmHg at 25 °C HSDB
0.3 mmHg at 25 °C ICSC
Flash point 105 °C (221 °F) HSDB
105.56 °C (222 °F) NIOSH
110 °C (230 °F) CAMEO
Autoignition temperature 571 °C (1059.8 °F) HSDB
571.11 °C (1060 °F) CAMEO
Lower explosive limit (LEL) 2.5 % by volume DOE PAC
2.5 % by volume at 150 °C HSDB
Upper explosive limit (UEL) 6.6 % by volume at 150 °C HSDB
Vapor density 6.26 (air = 1) HSDB
Odor threshold Industrial data report an odor threshold of approx 3 ppm ... HSDB
Low odor threshold= 24.0 mg/cu m; High odor threshold= 24.0 mg/cu m; Irritating concn= 40.0 mg/cu m HSDB
Odor Threshold Low: 2.96 [ppm] Haz-Map
Critical temperature and pressure 453.3 °C (847.9 °F) HSDB

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

04 · Handling and storage

Storing and handling 1,2,4-Trichlorobenzene

Storage conditions

1,2,4-Trichlorobenzenes are liquids at room temperature and are shipped in bulk in aluminum tank trucks and steel or stainless steel tank cars.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

... On contact with acids or acid fumes they evolve highly toxic /hydrogen chloride/ fumes. /chlorides/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

1,2,4-TRICHLOROBENZENE can react vigorously with oxidizing materials (NTP, 1992). Yields hydrogen chloride and phosgene when heated to decomposition (USCG, 1999).

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check 1,2,4-Trichlorobenzene in the storage compatibility matrix →

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