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

Propionic Acid

Propionic Acid is colorless, oily liquid with a slightly pungent disagreeable, rancid odor.

CAS 79-09-4 C3H6O2 74.08 g/mol Danger

01 · Identification

What Propionic Acid is

Propionic Acid is colorless, oily liquid with a slightly pungent disagreeable, rancid odor. Its molecular formula is C3H6O2 and its molecular weight is 74.08 g/mol. It boils at 141 °C, melts at -21.5 °C.

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

CAS number79-09-4
EC number201-176-3
Index number607-089-00-0
Molecular formulaC3H6O2
Molecular weight74.08 g/mol
Chemical class Corrosives

Other names for Propionic Acid

  • propionic acid … %

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 Propionic Acid
CodeHazard statement
H314 Causes severe skin burns and eye damage.

Precautionary statements: P260, P280, P301, P310, P331

03 · Physical and chemical properties

Propionic 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 141.1 °C (286 °F) HSDB
141.11 °C (286 °F) NIOSH
140.72 °C (285.3 °F) at 760 mmHg CAMEO
Melting point -21.5 °C (-6.7 °F) HSDB
-15 °C (5 °F) NIOSH
Density 0.315 g/cm³ HSDB
0.99 g/cm³ NIOSH
0.993 g/cm³ at 20 °C HSDB
Solubility Sol in alcohol, ether, chloroform. HSDB
Miscible with ethanol; soluble in diethyl ether; slightly soluble in chloroform HSDB
Vapor pressure 3 mmHg NIOSH
2.9 mmHg at 20 °C CAMEO
3.53 mmHg at 25 °C HSDB
Flash point 52.22 °C (126 °F) HSDB
54.44 °C (130 °F) CAMEO
Autoignition temperature 465.56 °C (870 °F) HSDB
485 °C (905 °F) ICSC
Lower explosive limit (LEL) 2.9 % by volume HSDB
Upper explosive limit (UEL) 12.1 % by volume HSDB
14.8 % by volume CAMEO
Vapor density 2.56 (air = 1) HSDB
2.6 (air = 1) ICSC
Odor threshold Odor threshold: 0.16 ul/l; Odor safety class B; B= 50-90% of distracted persons perceive warning of TLV. HSDB
0.0840 mg/cu m (odor low); 60.00 mg/cu m (odor high). HSDB
Odor Threshold Low: 0.02 [ppm] Haz-Map
Critical temperature and pressure 338.9 °C (642 °F) HSDB
Corrosivity CORROSIVE HSDB

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

04 · Handling and storage

Storing and handling Propionic Acid

Storage conditions

Outside or detached storage is preferred. Store in a cool, dry, well-ventilated location.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Alkalis, strong oxidizers (e.g., chromium trioxide) [Note: Corrosive to steel].

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

PROPIONIC ACID is a colorless, oily liquid, moderately toxic, corrosive. Flammable when exposed to heat, flame or oxidizers. When heated to decomposition it emits acrid smoke and irritating fumes [Lewis, 3rd ed., 1993, p. 1090].

Source: CAMEO Chemicals

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

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