Tetrachloroethylene

• Formula: C₂Cl₄
• Molecular weight: 165.833
• IUPAC Standard InChI: InChI=1S/C2Cl4/c3-1(4)2(5)6 Copy

  
• IUPAC Standard InChIKey: CYTYCFOTNPOANT-UHFFFAOYSA-N Copy
• CAS Registry Number: 127-18-4
• 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: Ethene, tetrachloro-; Ethylene, tetrachloro-; Ankilostin; Antisal 1; Didakene; Ethylene tetrachloride; Fedal-Un; Nema; Perchlorethylene; Perchloroethylene; Perclene; PerSec; Tetlen; Tetracap; Tetrachlorethylene; Tetrachloroethene; Tetraguer; Tetraleno; Tetropil; 1,1,2,2-Tetrachloroethylene; C2Cl4; Carbon bichloride; Carbon dichloride; Czterochloroetylen; ENT 1,860; Nema, veterinary; NCI-C04580; Perawin; Perchloorethyleen, per; Perchloraethylen, per; Perchlorethylene, per; Percloroetilene; PERC; Tetrachlooretheen; Tetrachloraethen; Tetracloroetene; Tetralex; Antisol 1; Dow-per; Perchlor; Perclene D; Percosolve; PERK; Perklone; RCRA Waste Number U210; Tetravec; Tetroguer; UN 1897; Dilatin PT; 1,1,2,2-Tetrachloroethene; Freon 1110; Perclene TG; Perchloroethene; F 1110
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas Chromatography
• Data at other public NIST sites:
  • 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, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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

Constant pressure heat capacity of liquid

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
BS - Robert L. Brown and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Enthalpy of fusion

Entropy of fusion

Entropy of fusion

Enthalpy of phase transition

Entropy of phase transition

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

=  + 

By formula: C₂HCl₅ = C₂Cl₄ + HCl

 +  =

By formula: C₂Cl₄ + Cl₂ = C₂Cl₆

H₂CaO₂ + 2 = CaCl₂ + 2 + 2

By formula: H₂CaO₂ + 2C₂HCl₅ = CaCl₂ + 2C₂Cl₄ + 2H₂O

=  + 

By formula: C₂Cl₆ = C₂Cl₄ + Cl₂

Henry's Law data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
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
B - John E. Bartmess

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compiled by: Coblentz Society, Inc.

• Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• GAS (13 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg); DOW KBr FOREPRISM-GRATING; DIGITIZED BY COBLENTZ SOCIETY (BATCH II) FROM HARD COPY; 2 cm^-1 resolution
• SOLUTION (10% IN CCl4 FOR 3800-1300, AND 10% IN CS2 FOR 1300-650 CM^-1) VERSUS SOLVENT; PERKIN-ELMER 521 (GRATING); DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Data compiled by: Pamela M. Chu, Franklin R. Guenther, George C. Rhoderick, and Walter J. Lafferty

• gas; IFS66V (Bruker); 3-Term B-H Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); Boxcar Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); Happ Genzel Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); NB Strong Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution
• gas; IFS66V (Bruker); Triangular Apodization
  0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm^-1 resolution

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, UV/Visible spectrum, Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

UV/Visible spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

Vibrational and/or electronic energy levels

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Takehiko Shimanouchi

Symmetry:   D_2h     Symmetry Number σ = 4

Source: Shimanouchi, 1972

Notes

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Manion, 2002
Manion, J.A., Evaluated Enthalpies of Formation of the Stable Closed Shell C1 and C2 Chlorinated Hydrocarbons, J. Phys. Chem. Ref. Data, 2002, 31, 1, 123-172, https://doi.org/10.1063/1.1420703 . [all data]

Kirkbride, 1956
Kirkbride, F.W., The heats of chlorination of some hydrocarbons and their chloro-derivatives, J. Appl. Chem., 1956, 6, 11-21. [all data]

Smith, Bjellerup, et al., 1953
Smith, L.; Bjellerup, L.; Krook, S.; Westermark, H., Heats of combustion of organic chloro compounds determined by the "quartz wool" method, Acta Chem. Scand., 1953, 7, 65. [all data]

Novoselova, Rabinovich, et al., 1986
Novoselova, N.V.; Rabinovich, I.B.; Tsvetkova, L.Ya.; Moseeva, E.M.; Babinkov, A.G., Heat capacity and thermodynamic functions of tetrachloroethylene, Zhur. Fiz. Khim., 1986, 60, 1627-1630. [all data]

Wilhelm, Lainez, et al., 1989
Wilhelm, E.; Lainez, A.; Grolier, J.-P.E., Thermodynamics of (a halogenated ethane or ethene + an n-alkane). VE and CpE of mixtures containing either 1,1,2,2-tetrachloroethane or tetrachloroethene, Fluid Phase Equilib., 1989, 49, 233-250. [all data]

Grolier, Inglese, et al., 1982
Grolier, J.-P.E.; Inglese, A.; Wilhelm, E., Excess volumes and excess heat capacities of tetrachloroethene + cyclohexane, + methylcyclohexane, + benzene, and + toluene at 298.15 K, J. Chem. Thermodynam., 1982, 14, 523-529. [all data]

Kurbatov, 1948
Kurbatov, V.Ya., Heat capacity of liquids. 2. Heat capacity and the temperature dependence of heat capacity from halogen derivatives of acylic hydrocarbons, Zh. Obshch. Kim., 1948, 18, 372-389. [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]

Dreisbach and Martin, 1949
Dreisbach, R.R.; Martin, R.A., Physical Data on Some Organic Compounds, Ind. Eng. Chem., 1949, 41, 2875-8. [all data]

Van de Vloed, 1939
Van de Vloed, A., Bull. Soc. Chim. Belg., 1939, 48, 229. [all data]

Novoselova, Rabinovich, et al., 1986, 2
Novoselova, N.V.; Rabinovich, I.B.; Tsvetkova, L.Ya.; Moseeva, E.M.; Babinkov, A.G., Heat capacity and thermodynamic functions of tetrachloroethylene, Zh. Fiz. Khim., 1986, 60, 1627-30. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Majer, Sváb, et al., 1980
Majer, V.; Sváb, L.; Svoboda, V., Enthalpies of vaporization and cohesive energies for a group of chlorinated hydrocarbons, The Journal of Chemical Thermodynamics, 1980, 12, 9, 843-847, https://doi.org/10.1016/0021-9614(80)90028-2 . [all data]

Mathews, 1926
Mathews, J.H., The accurate measurement of heats of vaporization of liquids, J. Am. Chem. Soc., 1926, 48, 562-576. [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]

Dejoz, Cruz Burguet, et al., 1995
Dejoz, Ana; Cruz Burguet, M.; Munoz, Rosa; Sanchotello, Margarita, Isobaric Vapor-Liquid Equilibria of Tetrachloroethylene with 1-Butanol and 2-Butanol at 6 and 20 kPa, J. Chem. Eng. Data, 1995, 40, 1, 290-292, https://doi.org/10.1021/je00017a064 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Boublík and Aim, 1972
Boublík, T.; Aim, K., Heats of vaporization of simple non-spherical molecule compounds, Collect. Czech. Chem. Commun., 1972, 37, 11, 3513-3521, https://doi.org/10.1135/cccc19723513 . [all data]

Polak, Murakami, et al., 1970
Polak, Jiri; Murakami, Sachio; Lam, V.T.; Benson, George C., Excess enthalpy, volume, and Gibbs free energy of cyclopentane-tetrachloroethylene mixtures at 25.deg., J. Chem. Eng. Data, 1970, 15, 2, 323-328, https://doi.org/10.1021/je60045a041 . [all data]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [all data]

Fried, Gallant, et al., 1967
Fried, Vojtech; Gallant, Paul; Schneier, Gary B., Vapor-liquid equilibrium in the system pyridine-tetrachloroethylene, J. Chem. Eng. Data, 1967, 12, 4, 504-508, https://doi.org/10.1021/je60035a011 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Levanova, Bushneva, et al., 1979
Levanova, s.V.; Bushneva, I.I.; Rodova, R.M.; Rozhnov, A.M.; Treger, Yu.A.; Aprelkin, A.S., Thermodynamic stability of chloroethanes in dehydrochlorination reactions, J. Appl. Chem. USSR, 1979, 52, 1439-1442. [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]

Puyo, Balesdent, et al., 1963
Puyo, J.; Balesdent, D.; Niclause, M.; Dzierzynski, M., Etude analytique et thermodynamique de la pyrolyse de l'hexachloroethane en phase gazeuse., Compt. Rend., 1963, 256, 3471-3473. [all data]

Gossett, 1987
Gossett, J.M., Measurement of Henry's Law Constants for C1 and C2 Chlorinated Hydrocarbons, Environ. Sci. Technol., 1987, 21, 202-208. [all data]

Leighton and Calo, 1981
Leighton, D.T.; Calo, J.M., Distribution Coefficients of Chlorinated Hydrocarbons in Dilute Air-Water Systems for Groundwater Contamination Applications, J. Chem. Eng. Data, 1981, 26, 382-385. [all data]

Pearson and McConnell, 1975
Pearson, C.R.; McConnell, G., Chlorinated C1 and C2 Hydrocarbons in the Marine Environment, Proc. R. Soc. London, B, 1975, 189, 305-332. [all data]

Chen, Wiley, et al., 1994
Chen, E.C.M.; Wiley, J.R.; Batten, C.F.; Wentworth, W.E., Determination of the Electron Affinities of Molecules Using Negative Ion Mass Spectrometry, J. Phys. Chem., 1994, 98, 1, 88, https://doi.org/10.1021/j100052a016 . [all data]

Curtiss, Raghavachari, et al., 7374
Curtiss, L.A.; Raghavachari, K.; Redfern, P.C.; Pople, J.A., Assesment of Gaussian-3 and density Functional Theories for a larger experimental test set, J. Chem. Phys. 112 (2000), 7374. [all data]

Wiley, Chen, et al., 1991
Wiley, J.R.; Chen, E.C.M.; Chen, E.S.D.; Richardson, P.; Reed, W.R.; Wentworth, W.E., The Determination of Absolute Electron Affinities of Chlorobenzenes, Chloronaphthalenes and Chlorinated Biphenyls from Reduction Potentials, J. Electroanal. Chem. Interfac., 1991, 307, 1-2, 169, https://doi.org/10.1016/0022-0728(91)85546-2 . [all data]

Williams and Cool, 1990
Williams, B.A.; Cool, T.A., Multiphoton spectroscopy of Rydberg states of tetrachloroethylene, J. Chem. Phys., 1990, 93, 1521. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Lake and Thompson, 1970
Lake, R.F.; Thompson, H., Photoelectron spectra of halogenated ethylenes, Proc. Roy. Soc. (London), 1970, A315, 323. [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]

Bralsford, Harris, et al., 1960
Bralsford, R.; Harris, P.V.; Price, W.C., The effect of fluorine on the electronic spectra and ionization potentials of molecules, Proc. Roy. Soc. (London), 1960, A258, 459. [all data]

Von Niessen, Asbrink, et al., 1982
Von Niessen, W.; Asbrink, L.; Bieri, G., 30.4 nm He(II) Photoelectron spectra of organic molecules. Part VI. Halogeno-compounds (C,H,X: X = Cl, Br, I), J. Electron Spectrosc. Relat. Phenom., 1982, 26, 173. [all data]

Shapiro and Lossing, 1968
Shapiro, J.S.; Lossing, F.P., Free radicals by mass spectrometry. XXXVII. The ionization potential and heat of formation of dichlorocarbene, J. Phys. Chem., 1968, 72, 1552. [all data]

Lacher and Park, 1950
Lacher, J.R.; Park, J.D., J. Am. Chem. Soc., 1950, 72, 5486. [all data]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔHtrs	Enthalpy of phase transition
  ΔStrs	Entropy of phase transition
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization 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.