Acetic acid (data page)

Last updated February 07, 2026

This page provides supplementary chemical data on acetic acid.

Material Safety Data Sheet

The handling of this chemical may incur notable safety precautions. It is highly recommend that you seek the Material Safety Datasheet (MSDS) for this chemical from a reliable source and follow its directions.

Structure and properties

Dielectric constant, ε_r

6.15 ε₀ at 20 °C

Surface tension

26.6 dyn/cm at 30 °C

Viscosity ^[1]

1.222 mPa·s	at 20 °C
1.0396 mPa·s	at 30 °C
0.7956 mPa·s	at 50 °C
0.4244 mPa·s	at 110 °C

Thermodynamic properties

Phase behavior
Triple point	289.8 K (16.7 °C), ? Pa
Eutectic point with water	–26.7 °C
Std entropy change of fusionΔ_fusS^o	40.5 J/(mol·K)
Liquid properties
Standard molar entropy S^o_liquid	158.0 J/(mol K)
Gas properties
Std enthalpy change of formation Δ_fH^o_gas	–438.1 kJ/mol
Standard molar entropy S^o_gas	282.84 J/(mol K)
Heat capacity c_p	63.4 J/(mol K)
van der Waals' constants ^[2]	a = 1782.3 L² kPa/mol² b = 0.1068 liter per mole

Vapor pressure of liquid

P in mm Hg		1	10	40	100	400	760	1520	3800	7600	15200	30400	45600
T in °C		–17.2	17.5	43.0	63.0	99.0	118.1	143.5	180.3	214.0	252.0	297.0	—

Table data obtained from CRC Handbook of Chemistry and Physics 44th ed.

Acetic acid vapor pressure vs. temperature. Uses formula:
P
m
m
H
g
=
10
7.80307
-
1651.2
225
+
T
{\displaystyle \scriptstyle P_{mmHg}=10^{7.80307-{\frac {1651.2}{225+T}}}}
for T = 0 to 36 degC
P
m
m
H
g
=
10
7.18807
-
1416.7
211
+
T
{\displaystyle \scriptstyle P_{mmHg}=10^{7.18807-{\frac {1416.7}{211+T}}}}
for T = 36 to 170 degC
Formula from Lange's Handbook of Chemistry, 10th ed. AceticAcidVaporPressure.png — Acetic acid vapor pressure vs. temperature. Uses formula: $\scriptstyle P_{mmHg}=10^{7.80307-{\frac {1651.2}{225+T}}}$ for T = 0 to 36 °C $\scriptstyle P_{mmHg}=10^{7.18807-{\frac {1416.7}{211+T}}}$ for T = 36 to 170 °C
Formula from *Lange's Handbook of Chemistry*, 10th ed.

log10 of acetic acid vapor pressure vs. temperature. Uses formula:
log
10
[?]
P
m
m
H
g
=
7.80307
-
1651.2
225
+
T
{\displaystyle \scriptstyle \log _{10}P_{mmHg}=7.80307-{\frac {1651.2}{225+T}}}
for T = 0 to 36 degC
log
10
[?]
P
m
m
H
g
=
7.18807
-
1416.7
211
+
T
{\displaystyle \scriptstyle \log _{10}P_{mmHg}=7.18807-{\frac {1416.7}{211+T}}}
for T = 36 to 170 degC
Formula from Lange's Handbook of Chemistry, 10th ed. LogAceticAcidVaporPressure.png — log₁₀ of acetic acid vapor pressure vs. temperature. Uses formula: $\scriptstyle \log _{10}P_{mmHg}=7.80307-{\frac {1651.2}{225+T}}$ for T = 0 to 36 °C $\scriptstyle \log _{10}P_{mmHg}=7.18807-{\frac {1416.7}{211+T}}$ for T = 36 to 170 °C
Formula from *Lange's Handbook of Chemistry*, 10th ed.

Distillation data

BP Temp. °C	mole % water
Vapor-liquid Equilibrium for Acetic acid/Water^[3] P = 760 mm Hg
BP Temp. °C	liquid	vapor
116.5	2.2	5.8
114.6	5.4	12.3
113.4	8.6	16.8
113.5	9.9	18.3
113.1	10.1	18.8
110.6	18.9	29.8
107.8	30.3	43.3
106.1	41.3	54.5
104.4	52.2	64.9
103.1	62.4	73.5
102.3	69.6	79.2
101.6	77.8	85.1
100.8	87.6	91.4
100.5	92.3	94.4
100.4	94.5	96.0
100.1	98.5	98.9

Spectral data

UV-Vis

λ_max

207 nm (gas phase)

IR

Major absorption bands^[4]

Wave number	transmittance
(liquid film)
2937 cm⁻¹	26%
2684 cm⁻¹	41%
2631 cm⁻¹	39%
2569 cm⁻¹	49%
1758 cm⁻¹	19%
1714 cm⁻¹	4%
1617 cm⁻¹	66%
1414 cm⁻¹	20%
1360 cm⁻¹	39%
1294 cm⁻¹	12%
1053 cm⁻¹	67%
1016 cm⁻¹	41%
937 cm⁻¹	35%
892 cm⁻¹	41%
629 cm⁻¹	31%
607 cm⁻¹	49%
481 cm⁻¹	36%
473 cm⁻¹	52%

NMR

Proton NMR

δ CDCl₃ 2.10 (3H), 11.42 (1H)

Carbon-13 NMR

δ CDCl₃ 20.8, 178.1

MS

Masses of
main fragments

60 (75%), 45 (90%),
43 (100%), 42 (13%), 15 (17%)

References

↑ Lange's Handbook of Chemistry, 10th ed. pp 1669-1674
↑ Lange's Handbook of Chemistry 10th ed, pp 1522-1524
↑ "Binary Vapor-Liquid Equilibrium Data". Chemical Engineering Research Information Center. Archived from the original (Queriable database) on 29 August 2007. Retrieved 5 May 2007.
↑ "Spectral Database for Organic Compounds". Advanced Industrial Science and Technology. Archived from the original (Queriable database) on 14 January 2013. Retrieved 9 June 2007.

Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD)
Orlando, John J.; Tyndall, Geoffrey S. (2003). "Gas phase UV absorption spectra for peracetic acid, and for acetic acid monomers and dimers". J. Photochem. Photobiol. A. 157 (2–3): 161–66. Bibcode:2003JPPA..157..161O. doi:10.1016/S1010-6030(03)00067-4. Archived from the original on April 11, 2023.

This box:

Except where noted otherwise, data relate to Standard temperature and pressure.
Reliability of data general note.

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.

[lange_1669-1] Lange's Handbook of Chemistry, 10th ed. pp 1669-1674

[lange1522-2] Lange's Handbook of Chemistry 10th ed, pp 1522-1524

[3] "Binary Vapor-Liquid Equilibrium Data". Chemical Engineering Research Information Center. Archived from the original (Queriable database) on 29 August 2007. Retrieved 5 May 2007.

[aist-4] "Spectral Database for Organic Compounds". Advanced Industrial Science and Technology. Archived from the original (Queriable database) on 14 January 2013. Retrieved 9 June 2007.

[1]

[2]

[3]

[4]