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

Ethanethiol

Ethanethiol is a colorless liquid with a leek-like odor.

CAS 75-08-1 C2H6S 62.14 g/mol Danger

01 · Identification

What Ethanethiol is

Ethanethiol is a colorless liquid with a leek-like odor. Its molecular formula is C2H6S and its molecular weight is 62.14 g/mol. It boils at 35.1 °C, melts at -148 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as flammable agents - 4th degree.

CAS number75-08-1
EC number200-837-3
Index number016-022-00-9
Molecular formulaC2H6S
Molecular weight62.14 g/mol
Chemical class Flammable agents - 4th degree

Other names for Ethanethiol

  • ethyl mercaptan

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 Ethanethiol
CodeHazard statement
H224 Extremely flammable liquid and vapour.
H331 Toxic if inhaled.
H302 Harmful if swallowed.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

Precautionary statements: P210, P233, P241, P242, P260, P270, P271, P273, P301, P304, P310, P312, P330, P391, P403, P501

03 · Physical and chemical properties

Ethanethiol 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 35.1 °C (95.2 °F) HSDB
30.46 °C (86.8 °F) HSDB
35 °C (95 °F) NIOSH
Melting point -147.8 °C (-234 °F) HSDB
-144.44 °C (-228 °F) NIOSH
-147.78 °C (-234 °F) CAMEO
Density 0.84 g/cm³ NIOSH
0.826 g/cm³ at 20 °C CAMEO
0.8315 g/cm³ at 25 °C HSDB
Solubility Soluble in alcohol, ether, petroleum naphtha HSDB
Soluble in acetone, dilute alkali HSDB
In water, 15,603 mg/L at 25 °C at 25 °C HSDB
Vapor pressure 442 mmHg NIOSH
529 mmHg at 25 °C, Extrapolated HSDB
Flash point -48.3 °C (-54.9 °F) Closed cup HSDB
-54 °C (-65.2 °F) Closed cup HSDB
-48.33 °C (-55 °F) NIOSH
Autoignition temperature 298.9 °C (570 °F) HSDB
300 °C (572 °F) CAMEO
299 °C (570.2 °F) ICSC
Lower explosive limit (LEL) 2.8 % by volume HSDB
Upper explosive limit (UEL) 18 % by volume HSDB
Vapor density 2.14 (air = 1) HSDB
Odor threshold An odor threshold of 0.00076 ppm has been reported. HSDB
Minimum detectable concentration= 1 part in 50 billion parts of air. HSDB
0.0003 PPM HSDB
Critical temperature and pressure 225.5 °C (437.9 °F) HSDB

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

04 · Handling and storage

Storing and handling Ethanethiol

Storage conditions

Fireproof. Separated from strong oxidants, strong acids. Cool.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizers [Note: Reacts violently with calcium hypochlorite].

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

ETHYL MERCAPTAN reacts violently with calcium hypochlorite, May react vigorously with other oxidizing reagents. On contact with strong acids or when heated to decomposition it emits highly toxic fumes of sulfur oxides [Sax, 9th ed., 1996, p. 1575].

Source: CAMEO Chemicals

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

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