Propionic acid

Propionic acid
Simplified skeletal formula
Simplified skeletal formula
Full structural formula
Full structural formula
Ball-and-stick model
Ball-and-stick model
Space-filling model
Space-filling model
Names
Preferred IUPAC name
Propanoic acid
Other names
Carboxyethane
Ethanecarboxylic acid
Ethylformic acid
Metacetonic acid
Methylacetic acid
C3:0 (Lipid numbers)
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.001.070 Edit this at Wikidata
EC Number
  • Propionic acid: 201-176-3
E number E280 (preservatives)
  • Propionic acid: 1062
RTECS number
  • Propionic acid: UE5950000
UNII
  • InChI=1S/C3H6O2/c1-2-3(4)5/h2H2,1H3,(H,4,5) checkY
    Key: XBDQKXXYIPTUBI-UHFFFAOYSA-N checkY
  • Propionic acid: CCC(=O)O
  • Propionate: CCC(=O)[O-]
Properties
C3H6O2
Molar mass 74.079 g·mol−1
Appearance Colorless, oily liquid[1]
Odor Pungent, rancid, unpleasant[1]
Density 0.98797 g/cm3[2]
Melting point −20.5 °C (−4.9 °F; 252.7 K)[8]
Boiling point 141.15 °C (286.07 °F; 414.30 K)[8]
Sublimes at −48 °C
ΔsublHo = 74 kJ/mol[3]
8.19 g/g (−28.3 °C)
34.97 g/g (−23.9 °C)
Miscible (≥ −19.3 °C)[4]
Solubility Miscible in EtOH, ether, CHCl
3[5]
log P 0.33[6]
Vapor pressure 0.32 kPa (20 °C)[7]
0.47 kPa (25 °C)[6]
9.62 kPa (100 °C)[3]
4.45·10−4 L·atm/mol[6]
Acidity (pKa) 4.88[6]
-43.50·10−6 cm3/mol
1.3843[2]
Viscosity 1.175 cP (15 °C)[2]
1.02 cP (25 °C)
0.668 cP (60 °C)
0.495 cP (90 °C)[6]
Structure
Monoclinic (−95 °C)[9]
P21/c[9]
a = 4.04 Å, b = 9.06 Å, c = 11 Å[9]
α = 90°, β = 91.25°, γ = 90°
0.63 D (22 °C)[2]
Thermochemistry
152.8 J/mol·K[5][3]
191 J/mol·K[3]
−510.8 kJ/mol[3]
1527.3 kJ/mol[2][3]
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Corrosive
GHS labelling:[7]
GHS02: FlammableGHS05: CorrosiveGHS07: Exclamation mark
Danger
H314[7]
P280, P305+P351+P338, P310[7]
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
2
0
Flash point 54 °C (129 °F; 327 K)[7]
512 °C (954 °F; 785 K)
Lethal dose or concentration (LD, LC):
1370 mg/kg (mouse, oral)[5]
NIOSH (US health exposure limits):
PEL (Permissible)
 none[1]
REL (Recommended)
 TWA 10 ppm (30 mg/m3) ST 15 ppm (45 mg/m3)[1]
IDLH (Immediate danger)
 N.D.[1]
Related compounds
Acetic acid
Lactic acid
3-Hydroxypropionic acid
Tartronic acid
Acrylic acid
Butyric acid
Related compounds
 1-Propanol
Propionaldehyde
Sodium propionate
Propionic anhydride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Propionic acid (/proʊpiˈɒnɪk/, from the Greek words πρῶτος : prōtos, meaning "first", and πίων : píōn, meaning "fat"; also known as propanoic acid) is a naturally occurring carboxylic acid with chemical formula CH
3CH
2CO
2H. It is a liquid with a pungent and unpleasant smell somewhat resembling body odor. The anion CH
3CH
2CO−
2 as well as the salts and esters of propionic acid are known as propionates or propanoates.

About half of the world production of propionic acid is consumed as a preservative for both animal feed and food for human consumption. It is also useful as an intermediate in the production of other chemicals, especially polymers.

  1. ^ a b c d e NIOSH Pocket Guide to Chemical Hazards. "#0529". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ a b c d e Lagowski, J.J., ed. (2012). The Chemistry of Nonaqueous Solvents. Vol. III. Elsevier. p. 362. ISBN 978-0323151030.
  3. ^ a b c d e f Propanoic acid in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD) (retrieved 13 June 2014)
  4. ^ Seidell, Atherton; Linke, William F. (1919). Solubilities of Inorganic and Organic Compounds (2nd ed.). D. Van Nostrand Company. p. 569.
  5. ^ a b c "chemister.ru (archived copy)". Archived from the original on 9 October 2016. Retrieved 13 June 2014.
  6. ^ a b c d e CID 1032 from PubChem
  7. ^ a b c d e Sigma-Aldrich Co., Propionic acid. Retrieved on 13 June 2014.
  8. ^ a b Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0.
  9. ^ a b c Strieter, F. J.; Templeton, D. H.; Scheuerman, R. F.; Sass, R. L. (1962). "The crystal structure of propionic acid". Acta Crystallographica. 15 (12): 1233–1239. Bibcode:1962AcCry..15.1233S. doi:10.1107/S0365110X62003278.