Butanal

• Formula: C₄H₈O
• Molecular weight: 72.1057
• IUPAC Standard InChI: InChI=1S/C4H8O/c1-2-3-4-5/h4H,2-3H2,1H3 Copy

  
• IUPAC Standard InChIKey: ZTQSAGDEMFDKMZ-UHFFFAOYSA-N Copy
• CAS Registry Number: 123-72-8
• 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: Butyraldehyde; n-Butanal; n-Butyl aldehyde; n-Butyraldehyde; Butal; Butaldehyde; Butanaldehyde; Butyl aldehyde; Butyral; Butyric aldehyde; Butyrylaldehyde; n-C3H7CHO; Aldehyde butyrique; Aldeide butirrica; Butalyde; Butyraldehyd; NCI-C56291; UN 1129; 1-Butanal; Butan-1-al; NSC 62779
• 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
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • UV/Visible spectrum
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to SI units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• 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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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:
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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of vaporization

Antoine Equation Parameters

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

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

Enthalpy 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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - 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

C₄H₇O^- +  =

By formula: C₄H₇O^- + H⁺ = C₄H₈O

 +  = ( • )

By formula: NO^- + C₄H₈O = (NO^- • C₄H₈O)

 +  =  + 2

By formula: C₆H₁₄O₂ + H₂O = C₄H₈O + 2CH₄O

 +  =

By formula: H₂ + C₄H₆O = C₄H₈O

(CAS Reg. No. 26232-84-8 • 4294967295) +  = CAS Reg. No. 26232-84-8

By formula: (CAS Reg. No. 26232-84-8 • 4294967295C₄H₈O) + C₄H₈O = CAS Reg. No. 26232-84-8

 +  =

By formula: C₄H₈O + H₂ = C₄H₁₀O

 +  = ( • )

By formula: Mg⁺ + C₄H₈O = (Mg⁺ • C₄H₈O)

 + 2 =  + 

By formula: C₄H₈O + 2CH₄O = C₆H₁₄O₂ + H₂O

3 =

By formula: 3C₄H₈O = C₁₂H₂₄O₃

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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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

View reactions leading to C₄H₈O⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₄H₇O^- +  =

By formula: C₄H₇O^- + H⁺ = C₄H₈O

Ion clustering data

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), 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: Michael M. Meot-Ner (Mautner) and Sharon G. Lias

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = ( • )

By formula: Mg⁺ + C₄H₈O = (Mg⁺ • C₄H₈O)

 +  = ( • )

By formula: NO^- + C₄H₈O = (NO^- • C₄H₈O)

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, Ion clustering data, Mass spectrum (electron ionization), 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

Gas Phase 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

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

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, Ion clustering data, IR 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: 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

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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), Notes

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

Wiberg, Crocker, et al., 1991
Wiberg, K.B.; Crocker, L.S.; Morgan, K.M., Thermochemical studies of carbonyl compounds. 5. Enthalpies of reduction of carbonyl groups, J. Am. Chem. Soc., 1991, 113, 3447-3450. [all data]

Buckley and Cox, 1967
Buckley, E.; Cox, J.D., Chemical equilibria. Part 2.-Dehydrogenation of propanol and butanol, Trans. Faraday Soc., 1967, 63, 895-901. [all data]

Nicholson, 1960
Nicholson, G.R., 478. The heats of combustion of butanal and heptanal, J. Chem. Soc., 1960, 2377-2378. [all data]

Tjebbes, 1960
Tjebbes, J., Heats of combustion of butannal and some related compounds, Acta Chem. Scand., 1960, 14, 180-188. [all data]

Chermin, 1961
Chermin, H.A.G., Thermo data for petrochemicals. Part 27: Gaseous normal aldehydes. The important thermo properties are presented for all the gaseous normal aldehydes from formaldehyde through decaldehyde, Pet. Refin., 1961, 40, 181-184. [all data]

Buckley E., 1967
Buckley E., Chemical equilibria. Part 2. Dehydrogenation of propanol and butanol, Trans. Faraday Soc., 1967, 63, 895-901. [all data]

Vasil'ev and Lebedev, 1989
Vasil'ev, V.G.; Lebedev, B.V., Thermodynamics of butanal in the temperature range 0-330K, Zh. Obshch. Khim., 1989, 59(11), 2415-2420. [all data]

Parks, Kennedy, et al., 1956
Parks, G.S.; Kennedy, W.D.; Gates, R.R.; Mosley, J.R.; Moore, G.E.; Renquist, M.L., Thermal data on organic compounds. XXVI. Some heat capacity, entropy and free energy data for seven compounds containing oxygen., Not In System, 1956, 78, 56-59. [all data]

Vasil'ev and Lebedev, 1989, 2
Vasil'ev, V.G.; Lebedev, B.V., Thermodynamics of butanal in the temperature range 0-330 K, Zh. Obshch. Khim., 1989, 59, 11, 2415. [all data]

Wilhoit, Chao, et al., 1985
Wilhoit, R.C.; Chao, J.; Hall, K.R., Thermodynamic Properties of Key Organic Compounds in the Carbon Range C1 to C4. Part 1. Properties of Condensed Phases, J. Phys. Chem. Ref. Data, 1985, 14, 1. [all data]

Parks, Kennedy, et al., 1956, 2
Parks, G.S.; Kennedy, W.D.; Gates, R.R.; Mosley, J.R.; Moore, G.E.; Renquist, M.L., Thermal Data on Organic Compounds XXVI. Some Heat Capacity, Entropy and Free Energy Data for Seven Compounds Containing Oxygen, J. Am. Chem. Soc., 1956, 78, 56-9. [all data]

Anselme and Teja, 1990
Anselme, M.J.; Teja, A.S., The critical properties of rapidly reacting substances, AIChE Symp. Ser., 1990, 86, 279, 128-32. [all data]

Teja and Rosenthal, 1990
Teja, A.S.; Rosenthal, D.J., The Critical Pressures and Temperatures of Twelve Substances Using A Low Residence Time Flow Apparatus, AIChE Symp. Ser., 1990, 86, 279, 133-7. [all data]

Chickos, Hosseini, et al., 1995
Chickos, James S.; Hosseini, Sarah; Hesse, Donald G., Determination of vaporization enthalpies of simple organic molecules by correlations of changes in gas chromatographic net retention times, Thermochimica Acta, 1995, 249, 41-62, https://doi.org/10.1016/0040-6031(95)90670-3 . [all data]

Buckley and Cox, 1967, 2
Buckley, E.; Cox, J.D., Chemical equilibria. Part 2.?Dehydrogenation of propanol and butanol, Trans. Faraday Soc., 1967, 63, 895, https://doi.org/10.1039/tf9676300895 . [all data]

Verevkin, Krasnykh, et al., 2003
Verevkin, Sergey P.; Krasnykh, Eugen L.; Vasiltsova, Tatiana V.; Koutek, Bohumir; Doubsky, Jan; Heintz, Andreas, Vapor pressures and enthalpies of vaporization of a series of the linear aliphatic aldehydes, Fluid Phase Equilibria, 2003, 206, 1-2, 331-339, https://doi.org/10.1016/S0378-3812(03)00035-9 . [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]

Wojtasinski, 1963
Wojtasinski, Jerome G., Measurement of Total Pressures for Determining Liquid-Vapor Equilibrium Relations of the Binary System Isobutyraldehyde n-Butyraldehyde., J. Chem. Eng. Data, 1963, 8, 3, 381-385, https://doi.org/10.1021/je60018a028 . [all data]

Seprakova, Paulech, et al., 1959
Seprakova, M.; Paulech, J.; Dykyj, J., Chem. Zvesti, 1959, 13, 5, 313. [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]

Kuchinskaya, 1938
Kuchinskaya, K., Vapor pressures of pure substances, Sbornik Trudov Opytnogo Zavoda im. Akad. S. V. Lebedeva, 1938, 27-30. [all data]

Seprakova, Paulech, et al., 1959, 2
Seprakova, M.; Paulech, J.; Dykyj, J., Dampfdruck der Butyraldehyde, Chem. Zvesti, 1959, 13, 313-316. [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]

Alconcel, Deyerl, et al., 2001
Alconcel, L.S.; Deyerl, H.J.; Continetti, R.E., Effects of alkyl substitution on the energetics of enolate anions and radicals, J. Am. Chem. Soc., 2001, 123, 50, 12675-12681, https://doi.org/10.1021/ja0120431 . [all data]

Zimmerman, Reed, et al., 1977
Zimmerman, A.H.; Reed, K.J.; Brauman, J.I., Photodetachment of electrons from enolate anions. Gas phase electron affinities of enolate radicals, J. Am. Chem. Soc., 1977, 99, 7203. [all data]

Reents and Freiser, 1981
Reents, W.D.; Freiser, B.S., Gas-Phase Binding Energies and Spectroscopic Properties of NO+ Charge-Transfer Complexes, J. Am. Chem. Soc., 1981, 103, 2791. [all data]

Farid and McMahon, 1978
Farid, R.; McMahon, T.B., Gas-Phase Ion-Molecule Reactions of Alkyl Nitrites by Ion Cyclotron Resonance Spectroscopy, Int. J. Mass Spectrom. Ion Phys., 1978, 27, 2, 163, https://doi.org/10.1016/0020-7381(78)80037-0 . [all data]

Wiberg, Morgan, et al., 1994
Wiberg, K.B.; Morgan, K.M.; Maltz, H., Thermochemistry of carbonyl reactions. 6. A study of hydration equilibria, J. Am. Chem. Soc., 1994, 116, 11067-11077. [all data]

Wiberg and Squires, 1981
Wiberg, K.B.; Squires, R.R., Thermochemical studies of carbonyl reactions. 2. Steric effects in acetal and ketal hydrolysis, J. Am. Chem. Soc., 1981, 103, 4473-4478. [all data]

Dolliver, Gresham, et al., 1938
Dolliver, M.A.; Gresham, T.L.; Kistiakowsky, G.B.; Smith, E.A.; Vaughan, W.E., Heats of organic reactions. VI. Heats of hydrogenation of some oxygen-containing compounds, J. Am. Chem. Soc., 1938, 60, 440-450. [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]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Operti, Tews, et al., 1988
Operti, L.; Tews, E.C.; Freiser, B.S., Determination of Gas-Phase Ligand Binding Energies to Mg+ by FTMS Techniques, J. Am. Chem. Soc., 1988, 110, 12, 3847, https://doi.org/10.1021/ja00220a020 . [all data]

Ogorodnikov, Katsnel'son, et al., 1990
Ogorodnikov, A.L.; Katsnel'son, M.G.; Pinson, V.V.; Levin, Yu.V., Study of thermodynamic characteristics of a butyraldehyde-cyclic trimer system, Zh. Prikl. Khim. (Leningrad), 1990, 63, 1340-1343. [all data]

Buttery, Ling, et al., 1969
Buttery, R.G.; Ling, L.C.; Guadagni, D.G., Volatilities Aldehydes, Ketones, and Esters in Dilute Water Solution, J. Agric. Food Chem., 1969, 17, 385-389. [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Desfrancois, Abdoul-Carime, et al., 1994
Desfrancois, C.; Abdoul-Carime, H.; Khelifa, N.; Schermann, J.P., Fork 1/r to 1/r2 Potentials: Electron Exchange between Rydberg Atoms and Polar Molecules, Phys. Rev. Lett., 1994, 73, 18, 2436, https://doi.org/10.1103/PhysRevLett.73.2436 . [all data]

Traeger and McAdoo, 1986
Traeger, J.C.; McAdoo, D.J., Decomposition thresholds and associated translational energy releases for eight C₄H₈O⁺ isomers, Int. J. Mass Spectrom. Ion Processes, 1986, 68, 35. [all data]

McAdoo and Hudson, 1983
McAdoo, D.J.; Hudson, C.E., The decompositions of metastable [C₄H₈O]⁺ ions and the [C₄H₈O]⁺ potential surface, Org. Mass Spectrom., 1983, 18, 466. [all data]

El-Sherbini, Allam, et al., 1981
El-Sherbini, T.M.; Allam, S.H.; Migahed, M.D.; Dawoud, A.M., Mass spectrometric investigation of aliphatic aldehydes, Z. Naturforsch. A:, 1981, 36, 1334. [all data]

Hernandez, Masclet, et al., 1977
Hernandez, R.; Masclet, P.; Mouvier, G., Spectroscopie de photoelectrons d'aldehydes et de cetones aliphatiques, J. Electron Spectrosc. Relat. Phenom., 1977, 10, 333. [all data]

Cocksey, Eland, et al., 1971
Cocksey, B.J.; Eland, J.H.D.; Danby, C.J., The effect of alkyl substitution on ionisation potential, J. Chem. Soc., 1971, (B), 790. [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]

Benoit and Harrison, 1977
Benoit, F.M.; Harrison, A.G., Predictive value of proton affinity. Ionization energy correlations involving oxygenated molecules, J. Am. Chem. Soc., 1977, 99, 3980. [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]

Holmes, Terlouw, et al., 1976
Holmes, J.L.; Terlouw, J.K.; Lossing, F.P., The thermochemistry of C₂H₄O⁺ ions, J. Phys. Chem., 1976, 80, 2860. [all data]

Mouvier and Hernandez, 1975
Mouvier, G.; Hernandez, R., Ionisation and appearance potentials of alkylketones, Org. Mass Spectrom., 1975, 10, 958. [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, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), 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
  Pc	Critical pressure
  S°gas	Entropy of gas at standard conditions
  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
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

• 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.