Butanoic acid
- Formula: C4H8O2
- Molecular weight: 88.1051
- IUPAC Standard InChIKey: FERIUCNNQQJTOY-UHFFFAOYSA-N
- CAS Registry Number: 107-92-6
- 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: Butyric acid; n-Butanoic acid; n-Butyric acid; Ethylacetic acid; Propylformic acid; 1-Butyric acid; 1-Propanecarboxylic acid; n-C3H7COOH; Propanecarboxylic acid; Butanic acid; Buttersaeure; Kyselina maselna; UN 2820; 1-Butanoic acid; NSC 8415
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Gas phase thermochemistry data
Go To: Top, Phase change data, Henry's Law data, Gas phase ion energetics data, 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.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -475.9 ± 4.0 | kJ/mol | N/A | Lebedeva, 1964 | Value computed using ΔfHliquid° value of -533.92±0.59 kj/mol from Lebedeva, 1964 and ΔvapH° value of 58±4 kj/mol from missing citation.; DRB |
ΔfH°gas | -475.9 ± 4.0 | kJ/mol | Ccb | Lebedeva, 1964 | Value computed using ΔfHliquid° from Lebedeva, 1964 and ΔvapH° value of 58. kJ/mol from Konicek and Wadso, 1970.; DRB |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 353.26 | J/mol*K | N/A | Stull D.R., 1969 | See [ Stull D.R., 1969], acrylic acid, C3H4O2.; GT |
Phase change data
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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
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 |
---|---|---|---|---|---|
Tboil | 436. ± 2. | K | AVG | N/A | Average of 53 out of 57 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 267.6 | K | N/A | Radwan and Hanna, 1976 | Uncertainty assigned by TRC = 0.2 K; TRC |
Tfus | 267.8 | K | N/A | Costello and Bowden, 1958 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 267.89 | K | N/A | Dreisbach and Martin, 1949 | Uncertainty assigned by TRC = 0.05 K; TRC |
Tfus | 267. | K | N/A | Timmermans, 1935 | Uncertainty assigned by TRC = 1.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 267.97 | K | N/A | Wilhoit, Chao, et al., 1985 | Uncertainty assigned by TRC = 0.05 K; TRC |
Ttriple | 268.03 | K | N/A | Martin and Andon, 1982 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.05 K; type of transition uncertain; TRC |
Ttriple | 267.4 | K | N/A | Parks and Anderson, 1926 | Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 615.2 | K | N/A | Andereya and Chase, 1990 | Uncertainty assigned by TRC = 2. K; TRC |
Tc | 624. | K | N/A | Ambrose and Ghiassee, 1987 | Uncertainty assigned by TRC = 1. K; TRC |
Tc | 631.77 | K | N/A | D'Souza and Teja, 1987 | Uncertainty assigned by TRC = 2.5 K; Ambrose's procedure; TRC |
Tc | 627.90 | K | N/A | Brown, 1906 | Uncertainty assigned by TRC = 6. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 40.64 | bar | N/A | Andereya and Chase, 1990 | Uncertainty assigned by TRC = 0.60 bar; TRC |
Pc | 39.50 | bar | N/A | Ambrose and Ghiassee, 1987 | Uncertainty assigned by TRC = 0.50 bar; TRC |
Pc | 40.9407 | bar | N/A | D'Souza and Teja, 1987 | Uncertainty assigned by TRC = 0.90 bar; Ambrose's procedure; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 59. ± 2. | kJ/mol | AVG | N/A | Average of 6 values; Individual data points |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
52.5 | 399. | N/A | Clifford, Ramjugernath, et al., 2004 | Based on data from 384. to 435. K.; AC |
50.3 | 406. | EB | Muñoz and Krähenbühl, 2001 | Based on data from 391. to 429. K.; AC |
58.5 ± 0.3 | 293. | GS | Verevkin, 2000 | Based on data from 278. to 308. K.; AC |
47.7 | 452. | A | Stephenson and Malanowski, 1987 | Based on data from 437. to 592. K.; AC |
51.1 | 316. | A | Stephenson and Malanowski, 1987 | Based on data from 301. to 358. K.; AC |
53.2 | 370. | A | Stephenson and Malanowski, 1987 | Based on data from 355. to 453. K. See also Dykyj, 1971.; AC |
52. | 378. | N/A | Dreisbach and Shrader, 1949 | Based on data from 363. to 436. K. See also Dreisbach and Martin, 1949, 2 and Boublik, Fried, et al., 1984.; AC |
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.
Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
293. to 423. | 6.10954 | 2634.471 | -3.471 | Jasper and Miller, 1955 | Coefficents calculated by NIST from author's data. |
364.07 to 436.40 | 4.90904 | 1793.898 | -70.564 | Dreisbach and Shrader, 1949 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
76.0 ± 1.5 | 248. | TE,ME | Calis-Van Ginkel, Calis, et al., 1978 | Based on data from 238. to 255. K.; AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
11.07 | 264.7 | Acree, 1991 | AC |
11.59 | 268. | Martin and Andon, 1982, 2 | AC |
11.071 | 267.4 | Parks and Anderson, 1926, 2 | DH |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
41.40 | 267.4 | Parks and Anderson, 1926, 2 | DH |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
1.040 | 155. to 230. | crystaline, II | crystaline, I | Martin and Andon, 1982, 2 | DH |
11.590 | 268.03 | crystaline, I | liquid | Martin and Andon, 1982, 2 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
5.06 | 155. to 230. | crystaline, II | crystaline, I | Martin and Andon, 1982, 2 | DH |
43.24 | 268.03 | crystaline, I | liquid | Martin and Andon, 1982, 2 | DH |
Henry's Law data
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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)
kH(T) = k°H exp(d(ln(kH))/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(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference |
---|---|---|---|
4700. | M | N/A | |
1900. | Q | N/A | |
1900. | M | N/A |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, 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:
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 C4H8O2+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 10.17 ± 0.05 | eV | N/A | N/A | L |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.17 ± 0.05 | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | LBLHLM |
10.24 | EI | Holmes, Fingas, et al., 1981 | LLK |
10.24 | EI | Holmes and Lossing, 1980 | LLK |
10.46 | PE | Watanabe, Yokoyama, et al., 1973 | LLK |
10.16 ± 0.05 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
10.38 | PE | Benoit and Harrison, 1977 | Vertical value; LLK |
10.22 | PE | Sustmann and Trill, 1972 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C2H4+ | 11.5 ± 0.1 | C2H4O2 | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
C2H4O2+ | 10.42 ± 0.05 | C2H4 | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
C2H4O2+ | 10.60 | C2H4 | EI | Holmes and Lossing, 1980 | LLK |
C2H5+ | 11.6 ± 0.1 | C2H3O2 | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
C2H402+ | 10.60 ± 0.05 | C2H4 | EI | Holmes and Lossing, 1980, 2 | LLK |
C3H5O2+ | 10.5 ± 0.1 | CH3 | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
C3H6+ | 11.4 ± 0.1 | CH2O2 | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
C3H7+ | 10.96 ± 0.05 | COOH | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
C4H7O+ | 11.8 ± 0.1 | OH | PIPECO | Butler, Fraser-Monteiro, et al., 1982 | T = 298K; LBLHLM |
De-protonation reactions
C4H7O2- + =
By formula: C4H7O2- + H+ = C4H8O2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1451. ± 8.4 | kJ/mol | TDEq | Norrman and McMahon, 1999 | gas phase; B |
ΔrH° | 1450. ± 9.2 | kJ/mol | G+TS | Caldwell, Renneboog, et al., 1989 | gas phase; B |
ΔrH° | 1450. ± 9.2 | kJ/mol | G+TS | Cumming and Kebarle, 1978 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1420. ± 8.4 | kJ/mol | IMRE | Caldwell, Renneboog, et al., 1989 | gas phase; B |
ΔrG° | 1420. ± 8.4 | kJ/mol | IMRE | Cumming and Kebarle, 1978 | gas phase; B |
References
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Lebedeva, 1964
Lebedeva, N.D.,
Heats of combustion of monocarboxylic acids,
Russ. J. Phys. Chem. (Engl. Transl.), 1964, 38, 1435-1437. [all data]
Konicek and Wadso, 1970
Konicek, J.; Wadso, I.,
Enthalpies of vaporization of organic compounds. VII. Some carboxylic acids,
Acta Chem. Scand., 1970, 24, 2612-26. [all data]
Stull D.R., 1969
Stull D.R., Jr.,
The Chemical Thermodynamics of Organic Compounds. Wiley, New York, 1969. [all data]
Radwan and Hanna, 1976
Radwan, M.H.; Hanna, A.A.,
Binary Azeotropes Containing Butyric Acid,
J. Chem. Eng. Data, 1976, 21, 285-8. [all data]
Costello and Bowden, 1958
Costello, J.M.; Bowden, S.T.,
The temperature variation of orthobaric density difference in liquid- vapour systems: IV fatty acids,
Recl. Trav. Chim. Pays-Bas, 1958, 77, 803. [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]
Timmermans, 1935
Timmermans, J.,
Researches in Stoichiometry. I. The Heat of Fusion of Organic Compounds.,
Bull. Soc. Chim. Belg., 1935, 44, 17-40. [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]
Martin and Andon, 1982
Martin, J.F.; Andon, R.J.L.,
Thermodynamic properties of organic oxygen compounds. Part LII. Molar heat capacity of ethanoic, propanoic, and butanoic acids.,
J. Chem. Thermodyn., 1982, 14, 679-88. [all data]
Parks and Anderson, 1926
Parks, G.S.; Anderson, C.T.,
Thermal data on organic compounds. III. The heat capacities, entropies and free energies of tertiary butyl alcohol, mannitol, erythritol and normal butyric acid,
J. Am. Chem. Soc., 1926, 48, 1506-12. [all data]
Andereya and Chase, 1990
Andereya, E.; Chase, J.D.,
Chem. Eng. Technol., 1990, 13, 304-12. [all data]
Ambrose and Ghiassee, 1987
Ambrose, D.; Ghiassee, N.B.,
Vapor Pressures and Critical Temperatures and Critical Pressures of Some Alkanoic Acids: C1 to C10,
J. Chem. Thermodyn., 1987, 19, 505. [all data]
D'Souza and Teja, 1987
D'Souza, R.; Teja, A.S.,
The prediction of the vapor pressures of carboxylic acids,
Chem. Eng. Commun., 1987, 61, 13. [all data]
Brown, 1906
Brown, J.C.,
The critical temperature and value of ml/theta of some carbon compounds,
J. Chem. Soc., Trans., 1906, 89, 311. [all data]
Clifford, Ramjugernath, et al., 2004
Clifford, Scott L.; Ramjugernath, Deresh; Raal, J. David,
Subatmospheric Vapor Pressure Curves for Propionic Acid, Butyric Acid, Isobutyric Acid, Valeric Acid, Isovaleric Acid, Hexanoic Acid, and Heptanoic Acid,
J. Chem. Eng. Data, 2004, 49, 5, 1189-1192, https://doi.org/10.1021/je034180e
. [all data]
Muñoz and Krähenbühl, 2001
Muñoz, Laura A.L.; Krähenbühl, M. Alvina,
Isobaric Vapor Liquid Equilibrium (VLE) Data of the Systems n -Butanol + Butyric Acid and n -Butanol + Acetic Acid,
J. Chem. Eng. Data, 2001, 46, 1, 120-124, https://doi.org/10.1021/je000033u
. [all data]
Verevkin, 2000
Verevkin, S.P.,
Measurement and Prediction of the Monocarboxylic Acids Thermochemical Properties,
J. Chem. Eng. Data, 2000, 45, 5, 953-960, https://doi.org/10.1021/je990282m
. [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]
Dykyj, 1971
Dykyj, J.,
Petrochemia, 1971, 11, 2, 27. [all data]
Dreisbach and Shrader, 1949
Dreisbach, R.R.; Shrader, S.A.,
Vapor Pressure--Temperature Data on Some Organic Compounds,
Ind. Eng. Chem., 1949, 41, 12, 2879-2880, https://doi.org/10.1021/ie50480a054
. [all data]
Dreisbach and Martin, 1949, 2
Dreisbach, R.R.; Martin, R.A.,
Physical Data on Some Organic Compounds,
Ind. Eng. Chem., 1949, 41, 12, 2875-2878, https://doi.org/10.1021/ie50480a053
. [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]
Jasper and Miller, 1955
Jasper, Joseph J.; Miller, George B.,
The Vapor Pressure of Monofluoroacetic Acid,
J. Phys. Chem., 1955, 59, 5, 441-442, https://doi.org/10.1021/j150527a015
. [all data]
Calis-Van Ginkel, Calis, et al., 1978
Calis-Van Ginkel, C.H.D.; Calis, G.H.M.; Timmermans, C.W.M.; de Kruif, C.G.; Oonk, H.A.J.,
Enthalpies of sublimation and dimerization in the vapour phase of formic, acetic, propanoic, and butanoic acids,
The Journal of Chemical Thermodynamics, 1978, 10, 11, 1083-1088, https://doi.org/10.1016/0021-9614(78)90082-4
. [all data]
Acree, 1991
Acree, William E.,
Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation,
Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H
. [all data]
Martin and Andon, 1982, 2
Martin, J.F.; Andon, R.J.L.,
Thermodynamic properties of organic oxygen compounds. Part LII. Molar heat capacity of ethanoic, propanoic, and butanoic acids,
J. Chem. Thermodynam., 1982, 14, 679-688. [all data]
Parks and Anderson, 1926, 2
Parks, G.S.; Anderson, C.T.,
Thermal data on organic compounds. III. The heat capacities, entropies and free energies of tertiary butyl alcohol, mannitol, erythritol and normal butyric acid,
J. Am. Chem. Soc., 1926, 48, 1506-1512. [all data]
Butler, Fraser-Monteiro, et al., 1982
Butler, J.J.; Fraser-Monteiro, M.L.; Fraser-Monteiro, L.; Baer, T.; Hass, J.R.,
Thermochemistry and dissociation dynamics of state-selected C4H8O2+ Ions. 2. Butanoic acid,
J. Phys. Chem., 1982, 86, 747. [all data]
Holmes, Fingas, et al., 1981
Holmes, J.L.; Fingas, M.; Lossing, F.P.,
Towards a general scheme for estimating the heats of formation of organic ions in the gas phase. Part I. Odd-electron cations,
Can. J. Chem., 1981, 59, 80. [all data]
Holmes and Lossing, 1980
Holmes, J.L.; Lossing, F.P.,
Gas-phase heats of formation of keto and enol ions of carbonyl compounds.,
J. Am. Chem. Soc., 1980, 102, 1591. [all data]
Watanabe, Yokoyama, et al., 1973
Watanabe, I.; Yokoyama, Y.; Ikeda, S.,
Lone pair ionization potentials of carboxylic acids determined by He(I) photoelectron spectroscopy,
Bull. Chem. Soc. Jpn., 1973, 46, 1959. [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]
Sustmann and Trill, 1972
Sustmann, R.; Trill, H.,
Photoelektronenspektroskopische Bestimmung von Substituenten-Effekten. II. α,β-ungesattigte Carbonester,
Tetrahedron Lett., 1972, 42, 4271. [all data]
Holmes and Lossing, 1980, 2
Holmes, J.L.; Lossing, F.P.,
Thermochemistry and unimolecular reactions of ionized acetic acid and its enol in the gas phase.,
J. Am. Chem. Soc., 1980, 102, 3732. [all data]
Norrman and McMahon, 1999
Norrman, K.; McMahon, T.B.,
Intramolecular solvation of carboxylate anions in the gas phase,
J. Phys. Chem. A, 1999, 103, 35, 7008-7016, https://doi.org/10.1021/jp9908202
. [all data]
Caldwell, Renneboog, et al., 1989
Caldwell, G.; Renneboog, R.; Kebarle, P.,
Gas Phase Acidities of Aliphatic Carboxylic Acids, Based on Measurements of Proton Transfer Equilibria,
Can. J. Chem., 1989, 67, 4, 661, https://doi.org/10.1139/v89-092
. [all data]
Cumming and Kebarle, 1978
Cumming, J.B.; Kebarle, P.,
Summary of gas phase measurements involving acids AH. Entropy changes in proton transfer reactions involving negative ions. Bond dissociation energies D(A-H) and electron affinities EA(A),
Can. J. Chem., 1978, 56, 1. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy Pc Critical pressure S°gas Entropy of gas 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 ΔfH°gas Enthalpy of formation of gas 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 ΔsubH Enthalpy of sublimation ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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