Acetic acid

Acetic acid

Names
Preferred IUPAC name Acetic acid
Systematic IUPAC name Ethanoic acid
Other names Vinegar (when dilute); Hydrogen acetate; Methanecarboxylic acid
Identifiers
CAS Number	64-19-7 Y
3D model (Jmol)	Interactive image
3DMet	B00009
Abbreviations	AcOH
Beilstein Reference	506007
ChEBI	CHEBI:15366 Y
ChEMBL	ChEMBL539 Y
ChemSpider	171 Y
DrugBank	DB03166 Y
ECHA InfoCard	100.000.528
EC Number	200-580-7
E number	E260 (preservatives)
Gmelin Reference	1380
IUPHAR/BPS	1058
KEGG	D00010 N
MeSH	Acetic+acid
PubChem	176
RTECS number	AF1225000
UNII	Q40Q9N063P Y
UN number	2789
InChI InChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4) Y Key: QTBSBXVTEAMEQO-UHFFFAOYSA-N Y
SMILES CC(O)=O
Properties
Chemical formula	C2H4O2
Molar mass	60.05 g·mol−1
Appearance	Colourless liquid
Odor	Pungent/Vinegar-like
Density	1.049 g cm−3
Melting point	16 to 17 °C; 61 to 62 °F; 289 to 290 K
Boiling point	118 to 119 °C; 244 to 246 °F; 391 to 392 K
Solubility in water	Miscible
log P	-0.322
Acidity (pKa)	4.76
Basicity (pKb)	9.24 (basicity of acetate ion)
Magnetic susceptibility (χ)	-31.54·10−6 cm3/mol
Refractive index (nD)	1.371
Viscosity	1.22 mPa s
Dipole moment	1.74 D
Thermochemistry
Specific heat capacity (C)	123.1 J K−1 mol−1
Std molar entropy (So298)	158.0 J K−1 mol−1
Std enthalpy of formation (ΔfHo298)	-483.88—483.16 kJ mol−1
Std enthalpy of combustion (ΔcHo298)	-875.50—874.82 kJ mol−1
Pharmacology
ATC code	G01AD02 (WHO) S02AA10 (WHO)
Hazards
Safety data sheet	See: data page
GHS pictograms
GHS signal word	Danger
GHS hazard statements	H226, H314
GHS precautionary statements	P280, P305+351+338, P310
EU classification (DSD)	C
R-phrases	R10, R35
S-phrases	(S1/2), S23, S26, S45
NFPA 704	2 3 0
Flash point	40 °C (104 °F; 313 K)
Autoignition temperature	427 °C (801 °F; 700 K)
Explosive limits	4–16%
Lethal dose or concentration (LD, LC):
LD50 (median dose)	3.31 g kg−1, oral (rat)
LC50 (median concentration)	5620 ppm (mouse, 1 hr) 16000 ppm (rat, 4 hr)
US health exposure limits (NIOSH):
PEL (Permissible)	TWA 10 ppm (25 mg/m3)
REL (Recommended)	TWA 10 ppm (25 mg/m3) ST 15 ppm (37 mg/m3)
IDLH (Immediate danger)	50 ppm
Related compounds
Related carboxylic acids	Formic acid Propionic acid
Related compounds	Acetaldehyde Acetamide Acetic anhydride Acetonitrile Acetyl chloride Ethanol Ethyl acetate Potassium acetate Sodium acetate Thioacetic acid
Supplementary data page
Structure and properties	Refractive index (n), Dielectric constant (εr), etc.
Thermodynamic data	Phase behaviour solid–liquid–gas
Spectral data	UV, IR, NMR, MS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Acetamide
Acetic anhydride
Acetonitrile
Acetyl chloride
Ethanol
Ethyl acetate
Potassium acetate
Sodium acetate
Thioacetic acid

Acetic acid /əˈsiːtᵻk/, systematically named ethanoic acid /ˌɛθəˈnoʊᵻk/, is a colourless liquid organic compound with the chemical formula CH₃COOH (also written as CH₃CO₂H or C₂H₄O₂). When undiluted, it is sometimes called glacial acetic acid. Vinegar is roughly 3–9% acetic acid by volume, making acetic acid the main component of vinegar apart from water. Acetic acid has a distinctive sour taste and pungent smell. In addition to household vinegar, it is mainly produced as a precursor to polyvinyl acetate and cellulose acetate. Although it is classified as a weak acid, concentrated acetic acid is corrosive and can attack the skin.