Molecule
Name
Acetic acid
IUPAC name
Acetic acid
Secondary names
Ethanoic acid, Methanecarboxylic acid, Ethylic acid, Vinegar acid, CH3COOH, CH3CO2H, C2H4O2, AcOH
InChI
InChI=1S/C2H4O2/c1-2(3)4/h1H3,(H,3,4)
InChI key
QTBSBXVTEAMEQO-UHFFFAOYSA-N
CAS number
64-19-7
Formula
$CH_3COOH$
Chemical formula
CH3COOH
Structural formula
[CH3]C(=O)[OH]
Charge
0
Unpaired electrons
0
  Atom Name Number
$C$ Carbon 2
$H$ Hydrogen 4
$O$ Oxygen 2
Relations
  • no
Isotope mixture type
terrestrial abundance
Spin type
equilibrated
Spin quantum numbers
1/2 (para, E), 3/2 (ortho, A)
Equilibrium ortho/para ratio
2 (2/1)
Molar mass
60.052 $g/mol$
State STP
liquid
Protic
protic
Polarity
polar
Dipole
1.7 $D$
Molecule symmetry
Cs
Case
nonlinear-polyatomic
Vibrations number
18
Vibrations
Label Mode Bond Symmetry Degeneracy Fundamental frequency Observed frequency Observed frequency Harmonic frequency Activity IR Activity Raman Strength Comments
V1 stretching $-O-H$ $A_{}'$ no 3583.0 3583.0 active inactive m
V2 stretching $-C \leq H_3$ $A_{}'$ double 3051.0 3051.0 active active vw degenerate with $\nu_13$
V3 stretching sym. $-C \leq H_3$ $A_{}'$ no 2944.0 2944.0 active inactive vw
V4 stretching $>C=O$ $A_{}'$ no 1788.0 1788.0 active inactive vs
V5 deformation $-C \leq H_3$ $A_{}'$ double 1430.0 1430.0 active inactive shoulder - degenerate with $\nu_14$
V6 bending sym. $-C \leq H_3$ $A_{}'$ no 1382.0 1382.0 active inactive m
V7 bending $\eqslantgtr C-O-H$ $A_{}'$ no 1264.0 1264.0 active inactive m
V8 stretching $\eqslantgtr C-O-$ $A_{}'$ no 1182.0 1182.0 active inactive s
V9 bending asym. in-p (rocking) $-C \leq H_3$ $A_{}'$ no 989.0 989.0 active inactive m
V10 stretching $\eqslantgtr C-C\leq$ $A_{}'$ no 847.0 847.0 active inactive w
V11 deformation $O=C(-)-O-$ $A_{}'$ no 657.0 657.0 active inactive s
V12 deformation $\geq C-C(-)=O$ $A_{}'$ no 581.0 581.0 active inactive m
V13 stretching $-C \leq H_3$ $A$ double 2996.0 2996.0 active active vw degenerate with $\nu_2$
V14 deformation $-C \leq H_3$ $A$ double 1430.0 1430.0 active inactive shoulder - degenerate with $\nu_5$
V15 bending asym. in-p (rocking) $-C \leq H_3$ $A$ double 1048.0 active inactive w degenerate with $\nu_5$
V16 bending out-p $>C=O$ $A$ no 642.0 642.0 active inactive s
V17 deformation $\eqslantgtr C-O-$ $A$ no 534.0 534.0 active inactive m
V18 deformation $-C \leq H_3$ $A$ no 93.0 active inactive czlculated frequency
Publications
Chemical functions
  Function Number
$R-CH_3$ 1
$R-C(=O)-OH$ 1
Chemical bonds
  Bond Number
$\geq C-H$ 3
$\eqslantgtr C-C\leq$ 1
$>C=O$ 1
$\eqslantgtr C-O-$ 1
$-O-H$ 1