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

Thioglycolic Acid

Thioglycolic Acid is a colorless liquid with a strong, unpleasant odor.

CAS 68-11-1 C2H4O2S 92.12 g/mol Danger

01 · Identification

What Thioglycolic Acid is

Thioglycolic Acid is a colorless liquid with a strong, unpleasant odor. Its molecular formula is C2H4O2S and its molecular weight is 92.12 g/mol. It boils at 120 °C, melts at -16.5 °C, is miscible with water.

Under the GHS it carries the signal word Danger. It is classed as corrosives.

CAS number68-11-1
EC number200-677-4
Index number607-090-00-6
Molecular formulaC2H4O2S
Molecular weight92.12 g/mol
Chemical class Corrosives

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 Thioglycolic Acid
CodeHazard statement
H331 Toxic if inhaled.
H311 Toxic in contact with skin.
H301 Toxic if swallowed.
H314 Causes severe skin burns and eye damage.

Precautionary statements: P260, P270, P271, P280, P301, P302, P304, P310, P330, P331, P352

03 · Physical and chemical properties

Thioglycolic Acid 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 120 °C (248 °F) ICSC
120 °C (248 °F) at 20 mmHg (reduced pressure) HSDB
Melting point -16.5 °C (2.3 °F) HSDB
-16.67 °C (2 °F) NIOSH
Density 1.32 g/cm³ NIOSH
1.3253 g/cm³ at 20 °C HSDB
Solubility Miscible with water HSDB
Miscible with chloroform, benzene and many other organic solvents HSDB
Miscible with ethanol, and ethyl ether; slightly soluble in chloroform HSDB
Vapor pressure 0.0868 mmHg at 25 °C HSDB
9.7508 mmHg at 18 °C ICSC
Flash point 130 °C (266 °F) Closed cup HSDB
112.78 °C (235 °F) CAMEO
126 °C (258.8 °F) ICSC
Autoignition temperature 350 °C (662 °F) HSDB
Lower explosive limit (LEL) 5.9 % by volume HSDB
Vapor density 3.18 (air = 1) HSDB
3.2 (air = 1) ICSC
Corrosivity Corrosive HSDB

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

04 · Handling and storage

Storing and handling Thioglycolic Acid

Storage conditions

Keep container tightly closed in a dry and well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Recommended storage temperature: -20 °C

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Strong oxidizing agents, Strong acids

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

THIOGLYCOLIC ACID is readily oxidized by air (NTP, 1992). Reacts readily with other oxidizing agents as well in reactions that may generate toxic gases. Incompatible with diazo and azo compounds, halocarbons, isocyanates, aldehydes, alkali metals, nitrides, hydrides, and other strong reducing agents. Reactions with these materials may generate heat and toxic and flammable gases. May react with acids to liberate hydrogen sulfide. Neutralizes bases in exothermic reactions. Reacts with cyanides, sulfites, nitrites, thiosulfates to generate flammable and toxic gases and heat. Reacts with carbonates and bicarbonates.

Source: CAMEO Chemicals

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

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