Acetic acid (data page)

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.

• PTCL Safety web site
• Science Stuff

Structure and properties

Structure and properties
Index of refraction, nD	1.3716
Dielectric constant, εr	6.15 ε0 at 20 °C
Bond strength	?
Bond length	?
Bond angle	?
Magnetic susceptibility	?
Surface tension	26.6 dyn/cm at 30 °C
Viscosity	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
Critical point	593 K (320 °C), 57.8 bar
Eutectic point with water	–26.7 °C
Std enthalpy change of fusionΔfusHo	+11.7 kJ/mol
Std entropy change of fusionΔfusSo	40.5 J/(mol·K)
Std enthalpy change of vaporizationΔvapHo	+23.7 kJ/mol
Std entropy change of vaporizationΔvapSo	? J/(mol·K)
Solid properties
Std enthalpy change of formation ΔfHosolid	? kJ/mol
Standard molar entropy Sosolid	? J/(mol K)
Heat capacity cp	? J/(mol K)
Liquid properties
Std enthalpy change of formation ΔfHoliquid	−483.5 kJ/mol
Standard molar entropy Soliquid	158.0 J/(mol K)
Enthalpy of combustion, ΔcHo	–876.1 kJ/mol
Heat capacity cp	123.1 J/(mol K)
Gas properties
Std enthalpy change of formation ΔfHogas	–438.1 kJ/mol
Standard molar entropy Sogas	282.84 J/(mol K)
Heat capacity cp	63.4 J/(mol K)
van der Waals' constants	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: $\scriptstyle P_{mmHg}=10^{7.80307-{\frac {1651.2}{225+T}}}$ 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: $\scriptstyle \log _{10}P_{mmHg}=7.80307-{\frac {1651.2}{225+T}}$ 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

Vapor-liquid Equilibrium for Acetic acid/Water P = 760 mm Hg
BP Temp. °C	mole % water
	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
λmax	207 nm (gas phase)
Extinction coefficient, ε	?
IR
Major absorption bands	(liquid film) Wave number transmittance 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
Other NMR data
MS
Masses of main fragments	60 (75%), 45 (90%), 43 (100%), 42 (13%), 15 (17%)

References

• 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.

  This box:   

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