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Acetic acid

Chemical acid found in vinegarSample of acetic acid in a reagent bottleNames Preferred IUPAC nameAcetic acidSystematic IUPAC nameEthanoic acidOther names Vinegar (when diluted); Hydrogen acetate; Methanecarboxylic acid; Ethylic acidIdentifiers CAS Number64-19-73D model (JSmol)Interactive imageAbbreviations AcOH Beilstein Reference506007 ChEBICHEBI:15366ChEMBLChEMBL539ChemSpider171DrugBankDB03166ECHA InfoCard100.000.528EC Number200-580-7E numberE260 (preservatives)Gmelin Reference1380 IUPHAR/BPS1058KEGGC00033D00010MeSHAcetic+acidPubChemCID176RTECS numberAF1225000UNIIQ40Q9N063PUN number2789 CompTox Dashboard(EPA)DTXSID5024394InChIInChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4)Key: QTBSBXVTEAMEQO-UHFFFAOYSA-NSMILESCC(O)=OProperties Chemical formulaCH3COOH Molar mass60.052 g·mol Appearance Colourless liquid OdorOverpowering vinegar-like Density1.049 g/cm (liquid); 1.27 g/cm (solid) Melting point16 to 17 °C; 61 to 62 °F; 289 to 290 K Boiling point118 to 119 °C; 244 to 246 °F; 391 to 392 K Critical point (T, P) 593 K (320 °C), 57.8 bar Solubility in waterMisciblelog P−0.28 Vapor pressure1.54653947 kPa (20 °C) 11.6 mmHg (20 °C) Acidity (pKa) 4.756 Conjugate baseAcetateMagnetic susceptibility (χ)−31.54·10 cm/mol Refractive index (nD)1.371 (VD = 18.19) Viscosity1.22 mPa s 1.22 cP Dipole moment1.74 D Thermochemistry Heat capacity(C)123.1 J/(K⋅mol) Std molarentropy(S298)158.0 J/(K⋅mol) Std enthalpy offormation(ΔfH298)−483.88–483.16 kJ/mol Std enthalpy ofcombustion(ΔcH298)−875.50–874.82 kJ/mol-876.1 kJ/mol Enthalpy of fusion(ΔfHfus)11.7 kJ/mol Enthalpy of vaporization(ΔfHvap)23.7 kJ/mol Pharmacology ATC codeG01AD02 (WHO) S02AA10 (WHO) Legal statusAU: S2 (Pharmacy medicine) / Schedule 6, Schedule 5, Schedule 2 Appendix E, clause 3 Appendix F, clause 4Hazards GHS labelling: PictogramsSignal wordDangerHazard statementsH226, H314Precautionary statementsP280, P305+P351+P338, P310NFPA 704 (fire diamond) 320Flash point40 °C (104 °F; 313 K) Autoignitiontemperature427 °C (801 °F; 700 K) Explosive limits4–16% Lethal dose or concentration (LD, LC): LD50 (median dose)3.31 g/kg, oral (rat) LC50 (median concentration)5620 ppm (mouse, 1 h)16000 ppm (rat, 4 h) NIOSH (US health exposure limits): PEL (Permissible)TWA 10 ppm (25 mg/m) REL (Recommended)TWA 10 ppm (25 mg/m) ST 15 ppm (37 mg/m) IDLH (Immediate danger)50 ppm Related compounds Related carboxylic acidsFormic acidPropionic acidRelated compoundsAcetaldehydeAcetamideAcetic anhydrideChloroacetic acidAcetyl chlorideGlycolic acidEthyl acetatePotassium acetateSodium acetateThioacetic acidSupplementary data page Acetic acid (data page)Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).N verify ( ?)

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