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

O-Toluidine

O-Toluidine is a light yellow liquid becoming reddish brown on exposure to air and light with an aromatic aniline-like odor.

CAS 95-53-4 C7H9N 107.15 g/mol Danger

01 · Identification

What O-Toluidine is

O-Toluidine is a light yellow liquid becoming reddish brown on exposure to air and light with an aromatic aniline-like odor. Its molecular formula is C7H9N and its molecular weight is 107.15 g/mol. It boils at 200 °C, melts at -14.4 °C, is soluble in water.

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

CAS number95-53-4
EC number202-429-0
Index number612-091-00-X
Molecular formulaC7H9N
Molecular weight107.15 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for O-Toluidine

  • 2-aminotoluene

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 O-Toluidine
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H331 Toxic if inhaled.
H301 Toxic if swallowed.
H319 Causes serious eye irritation.
H400 Very toxic to aquatic life.

Precautionary statements: P201, P260, P264, P270, P271, P273, P280, P301, P304, P305, P308, P310, P313, P330, P337, P338, P391, P501

03 · Physical and chemical properties

O-Toluidine 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 200.3 °C (392.5 °F) HSDB
200 °C (392 °F) NIOSH
Melting point -14.41 °C (6.1 °F) HSDB
-23.7 °C (-10.7 °F) alpha form HSDB
-14.44 °C (6 °F) NIOSH
Density 1.01 g/cm³ NIOSH
0.9984 g/cm³ at 20 °C HSDB
0.998 g/cm³ at 20 °C CAMEO
Solubility Soluble in alcohol and ether HSDB
Miscible in ethanol, diethyl ether, carbon tetrachloride HSDB
Soluble in dilute acids HSDB
Vapor pressure 0.3 mmHg NIOSH
0.1 mmHg at 20 °C CAMEO
0.26 mmHg at 25 °C HSDB
Flash point 85 °C (185 °F) HSDB
Autoignition temperature 482.22 °C (900 °F) HSDB
480 °C (896 °F) ICSC
Lower explosive limit (LEL) 1.5 % by volume HSDB
Upper explosive limit (UEL) 7.5 % by volume HSDB
Vapor density 3.69 (air = 1) HSDB
3.7 (air = 1) ICSC
Odor threshold Odor Threshold Low: 0.02 [ppm] Haz-Map
Odor Threshold High: 6.6 [ppm] Haz-Map
Odor threshold from AIHA Haz-Map
Critical temperature and pressure 443.85 °C (830.9 °F) HSDB

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

04 · Handling and storage

Storing and handling O-Toluidine

Storage conditions

Before entering confined space where this chemical may be present, check to make sure that an explosive concentration does not exist. o-Toluidine must be stored to avoid contact with strong oxidizers (such as chlorine, bromine, and fluorine) because violent reactions occur. Store in tightly closed containers in a cool, well-ventilated area away from heat. Sources of ignition, such as smoking and open flames, are prohibited where o-toluidine is used, handled, or stored in a manner that could creats a potential fire or explosion hazard. A regulated, marked area should be established where this chemical is handled, used, or stored ...

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Hypergolic reaction with red fuming nitric acid. Can react with oxidizing materials.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

O-TOLUIDINE neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides. Emits very toxic oxides of nitrogen when heated to decomposition. Undergoes a hypergolic reaction with red fuming nitric acid [Kit and Evered, 1960, p. 239, 242].

Source: CAMEO Chemicals

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