Acetyl chloride

Formula: C₂H₃ClO
Molecular weight: 78.498
IUPAC Standard InChI: InChI=1S/C2H3ClO/c1-2(3)4/h1H3
IUPAC Standard InChIKey: WETWJCDKMRHUPV-UHFFFAOYSA-N
CAS Registry Number: 75-36-5
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript.
Other names: Ethanoyl chloride; Acetic chloride; CH3COCl; Acetic acid chloride; Rcra waste number U006; UN 1717; Acetic acid monochloride; UN1717 (DOT)
Permanent link for this species. Use this link for bookmarking this species for future reference.
Information on this page:
Other data available:
Data at other public NIST sites:
- Computational Chemistry Comparison and Benchmark Database
- Gas Phase Kinetics Database
Options:
- Switch to calorie-based units

Data at NIST subscription sites:

NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics data, References, Notes

Data compiled by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-251.3 ± 0.50	kJ/mol	Cm	Devore and O'Neal, 1969	Heat of hydrolysis
Δ_fH°_gas	-244. ± 0.8	kJ/mol	Cm	Pritchard and Skinner, 1950	Reanalyzed by Cox and Pilcher, 1970, Original value = -249. kJ/mol; Heat of hydrolysis at 298 K, see Carson and Skinner, 1949
Δ_fH°_gas	-246.6	kJ/mol	Cm	Carson and Skinner, 1949

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References, Notes

Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_liquid	-272.0 ± 0.50	kJ/mol	Cm	Devore and O'Neal, 1969	Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -275.2 ± 0.46 kJ/mol; Heat of hydrolysis; ALS
Δ_fH°_liquid	-274. ± 0.59	kJ/mol	Cm	Pritchard and Skinner, 1950	Reanalyzed by Cox and Pilcher, 1970, Original value = -277.2 kJ/mol; Heat of hydrolysis at 298 K, see Carson and Skinner, 1949; ALS
Δ_fH°_liquid	-275.2 ± 0.2	kJ/mol	Cm	Carson and Skinner, 1949	ALS

Constant pressure heat capacity of liquid

C_p,liquid (J/mol*K)	Temperature (K)	Reference	Comment
117.2	298.	von Reis, 1881	T = 289 to 343 K.; DH

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, References, Notes

Data evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	10.82 ± 0.04	eV	N/A	N/A	L

Ionization energy determinations

IE (eV)	Method	Reference	Comment
10.78	PI	Traeger, McLouglin, et al., 1982	LBLHLM
10.85 ± 0.05	PE	Chadwick and Katrib, 1974	LLK
11.05	CI	Cermak, 1968	RDSH
11.08 ± 0.06	EI	Foffani, Pignataro, et al., 1964	RDSH
11.02 ± 0.05	PI	Watanabe, Nakayama, et al., 1962	RDSH
11.03	PE	Kimura, Katsumata, et al., 1975	Vertical value; LLK
11.03	PE	Katsumata and Kimura, 1975	Vertical value; LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
C₂H₃O⁺	10.78	Cl	PI	Traeger, McLouglin, et al., 1982	LBLHLM
C₂H₃O⁺	11.25	Cl	EI	Haney and Franklin, 1969	RDSH

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Notes

Devore and O'Neal, 1969
Devore, J.A.; O'Neal, H.E., Heats of formation of the acetyl halides and of the acetyl radical, J. Phys. Chem., 1969, 73, 2644-2648. [all data]

Pritchard and Skinner, 1950
Pritchard, H.O.; Skinner, H.A., The heats of hydrolysis of the chloro-substituted acetyl chlorides, J. Chem. Soc., 1950, 272-276. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Carson and Skinner, 1949
Carson, A.S.; Skinner, H.A., 201. Carbon-halogen bond energies in the acetyl halides, J. Chem. Soc., 1949, 936-939. [all data]

Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P., Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]

von Reis, 1881
von Reis, M.A., Die specifische Wärme flüssiger organischer Verbindungen und ihre Beziehung zu deren Moleculargewicht, Ann. Physik [3], 1881, 13, 447-464. [all data]

Traeger, McLouglin, et al., 1982
Traeger, J.C.; McLouglin, R.G.; Nicholson, A.J.C., Heat of formation for acetyl cation in the gas phase, J. Am. Chem. Soc., 1982, 104, 5318. [all data]

Chadwick and Katrib, 1974
Chadwick, D.; Katrib, A., Photoelectron spectra of acetaldehyde and acetyl halides, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 39. [all data]

Cermak, 1968
Cermak, V., Penning ionization electron spectroscopy. I. Determination of ionization potentials of polyatomic molecules, Collection Czech. Chem. Commun., 1968, 33, 2739. [all data]

Foffani, Pignataro, et al., 1964
Foffani, A.; Pignataro, S.; Cantone, B.; Grasso, F., Ionization potentials and substituent effects for aromatic carbonyl compounds, Z. Physik. Chem. (Frankfurt), 1964, 42, 221. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Kimura, Katsumata, et al., 1975
Kimura, K.; Katsumata, S.; Yamazaki, T.; Wakabayashi, H., UV photoelectron spectra and sum rule consideration; out-of-plane orbitals of unsaturated compounds with planar-skeleton structure, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 41. [all data]

Katsumata and Kimura, 1975
Katsumata, S.; Kimura, K., Photoelectron spectra and sum rule consideration. Effect of chlorine substitution on ionization energies for chloroethanes, chloroacetaldehydes and chloroacetyl chlorides, J. Electron Spectrosc. Relat. Phenom., 1975, 6, 309. [all data]

Haney and Franklin, 1969
Haney, M.A.; Franklin, J.L., Excess energies in mass spectra of some oxygen-containing organic compounds, J. Chem. Soc. Faraday Trans., 1969, 65, 1794. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References

Symbols used in this document:

AE	Appearance energy
C_p,liquid	Constant pressure heat capacity of liquid
IE (evaluated)	Recommended ionization energy
Δ_fH°_gas	Enthalpy of formation of gas at standard conditions
Δ_fH°_liquid	Enthalpy of formation of liquid at standard conditions

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
Customer support for NIST Standard Reference Data products.