Propyne
- Formula: C3H4
- Molecular weight: 40.0639
- IUPAC Standard InChIKey: MWWATHDPGQKSAR-UHFFFAOYSA-N
- CAS Registry Number: 74-99-7
- 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. - Isotopologues:
- Other names: Methylacetylene; 1-Propyne; Allylene; Propine; CH3C≡CH; Acetylene, methyl-
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Gas phase thermochemistry 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 185.4 ± 0.88 | kJ/mol | Ccb | Wagman, Kilpatrick, et al., 1945 | Unpublished work of E. J. Prosen; ALS |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
33.37 | 50. | Thermodynamics Research Center, 1997 | p=1 bar. Recommended values are in good agreement with other statistically calculated values [ Wagman D.D., 1945, Daykin P.N., 1962].; GT |
36.69 | 100. | ||
42.44 | 150. | ||
48.56 | 200. | ||
57.65 | 273.15 | ||
60.73 | 298.15 | ||
60.95 | 300. | ||
72.54 | 400. | ||
82.61 | 500. | ||
91.23 | 600. | ||
98.69 | 700. | ||
105.22 | 800. | ||
110.96 | 900. | ||
116.01 | 1000. | ||
120.43 | 1100. | ||
124.31 | 1200. | ||
127.70 | 1300. | ||
130.67 | 1400. | ||
133.28 | 1500. |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
57.57 | 272.28 | Kistiakowsky G.B., 1940 | Other experimental values of heat capacity [ Kistiakowsky G.B., 1940, 2] were measured with large uncertainties.; GT |
61.00 | 299.59 | ||
65.10 | 332.83 | ||
69.12 | 369.21 |
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 250.0 ± 0.5 | K | AVG | N/A | Average of 18 out of 19 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 170.2 ± 0.6 | K | AVG | N/A | Average of 6 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 168.5 | K | N/A | Maass and Wright, 1921 | Uncertainty assigned by TRC = 0.3 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 402.4 ± 0.2 | K | N/A | Tsonopoulos and Ambrose, 1996 | |
Tc | 402.38 | K | N/A | Vohra, Kang, et al., 1962 | Uncertainty assigned by TRC = 0.05 K; TRC |
Tc | 401.1 | K | N/A | Maass and Wright, 1921 | Uncertainty assigned by TRC = 0.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 56.3 ± 0.2 | bar | N/A | Tsonopoulos and Ambrose, 1996 | |
Pc | 56.2759 | bar | N/A | Vohra, Kang, et al., 1962 | Uncertainty assigned by TRC = 0.0506 bar; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.1635 | l/mol | N/A | Tsonopoulos and Ambrose, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 6.12 ± 0.02 | mol/l | N/A | Tsonopoulos and Ambrose, 1996 | |
ρc | 6.113 | mol/l | N/A | Vohra, Kang, et al., 1962 | Uncertainty assigned by TRC = 0.01 mol/l; TRC |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
23.0 | 242. | A | Stephenson and Malanowski, 1987 | Based on data from 183. to 257. K.; AC |
20.8 | 272. | A | Stephenson and Malanowski, 1987 | Based on data from 257. to 402. K.; AC |
21.2 | 318. | A | Stephenson and Malanowski, 1987 | Based on data from 303. to 361. K.; AC |
21.9 | 374. | A | Stephenson and Malanowski, 1987 | Based on data from 359. to 402. K.; AC |
23.2 | 264. | A | Stephenson and Malanowski, 1987 | Based on data from 249. to 306. K.; AC |
22.1 | 275. | N/A | Reid, 1972 | AC |
23.9 | 240. | N/A | Van Hook, 1967 | Based on data from 162. to 255. K.; AC |
21.6 | 338. | N/A | Vohra, Kang, et al., 1962 | Based on data from 323. to 400. K.; AC |
23.4 | 235. | N/A | Booth, Burchfield, et al., 1933 | Based on data from 194. to 250. K. See also Boublik, Fried, et al., 1984.; AC |
21.4 | 230. | N/A | Maass and Wright, 1921 | Based on data from 200. to 260. K.; AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (bar)
T = temperature (K)
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Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
161.5 to 254.27 | 4.95219 | 1226.123 | -1.926 | van Hook, 1967 | Coefficents calculated by NIST from author's data. |
249.9 to 398. | 4.03069 | 818.384 | -46.457 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
Reaction thermochemistry 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:
B - John E. Bartmess
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
M - 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. 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
C3H3- + =
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1591. ± 8.8 | kJ/mol | G+TS | Gal, Decouzon, et al., 2001 | gas phase; B |
ΔrH° | 1597. ± 9.6 | kJ/mol | D-EA | Robinson, Polak, et al., 1995 | gas phase; B |
ΔrH° | 1595. ± 8.8 | kJ/mol | G+TS | Robinson, Polak, et al., 1995 | gas phase; Relative to MeOH at 375.0. isomerization accounted for in kinetic scheme; B |
ΔrH° | 1594. ± 8.8 | kJ/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1559. ± 8.4 | kJ/mol | IMRE | Gal, Decouzon, et al., 2001 | gas phase; B |
ΔrG° | 1562. ± 8.4 | kJ/mol | IMRE | Robinson, Polak, et al., 1995 | gas phase; Relative to MeOH at 375.0. isomerization accounted for in kinetic scheme; B |
ΔrG° | 1562. ± 8.4 | kJ/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -289.6 ± 0.63 | kJ/mol | Chyd | Conn, Kistiakowsky, et al., 1939 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -288.8 ± 0.59 kJ/mol; At 355 K; ALS |
By formula: Li+ + C3H4 = (Li+ • C3H4)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 119. | kJ/mol | ICR | Staley and Beauchamp, 1975 | gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 extrapolated; M |
By formula: C3H4 = C3H4
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -3.8 ± 2.1 | kJ/mol | Cm | Cordes and Gunzler, 1959 | gas phase; Reanalyzed by Cox and Pilcher, 1970, Original value = -3.4 kJ/mol; ALS |
By formula: Co+ + C3H4 = (Co+ • C3H4)
Enthalpy of reaction
ΔrH° (kJ/mol) | T (K) | Method | Reference | Comment |
---|---|---|---|---|
79.1 (+8.8,-0.) | CID | Haynes and Armentrout, 1994 | gas phase; ΔrH>=, guided ion beam CID; M |
(CAS Reg. No. 65887-19-6 • 4294967295) + = CAS Reg. No. 65887-19-6
By formula: (CAS Reg. No. 65887-19-6 • 4294967295C3H4) + C3H4 = CAS Reg. No. 65887-19-6
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 141. ± 8.8 | kJ/mol | N/A | DePuy, Gronert, et al., 1989 | gas phase; B |
IR Spectrum
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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: Coblentz Society, Inc.
Gas Phase Spectrum
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Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.
Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.
Additional Data
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Owner | Copyright (C) 1987 by the Coblentz Society Collection (C) 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | DOW CHEMICAL COMPANY |
Source reference | COBLENTZ NO. 8880 |
Date | 1964 |
Name(s) | 1-propyne |
State | GAS (50 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg) |
Instrument | DOW KBr FOREPRISM-GRATING |
Instrument parameters | GRATING CHANGED AT 5.0, 7.5, 15.0 MICRON |
Path length | 5 CM SPECTRAL CONTAMINATION DUE TO ACETYLENE AT 732 CM-1 ROTATIONAL FEATURES BETWEEN 3090-2971 CM-1 ARE DELETED |
Resolution | 2 |
Sampling procedure | TRANSMISSION |
Data processing | DIGITIZED BY COBLENTZ SOCIETY (BATCH II) FROM HARD COPY |
Mass spectrum (electron ionization)
Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR 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
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Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
NIST MS number | 18849 |
Vibrational and/or electronic energy levels
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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: Takehiko Shimanouchi
Symmetry: C3ν Symmetry Number σ = 3
Sym. | No | Approximate | Selected Freq. | Infrared | Raman | Comments | ||||
---|---|---|---|---|---|---|---|---|---|---|
Species | type of mode | Value | Rating | Value | Phase | Value | Phase | |||
a1 | 1 | CH str | 3334 | C | 3334 | gas | 3305 M | liq. | ||
a1 | 2 | CH3 s-str | 2918 | E | 2941 M | gas | 2941 VS p | liq. | FR(ν2+2ν7) | |
a1 | 2 | CH3 s-str | 2918 | E | 2881 M | gas | 2941 VS p | liq. | FR(ν2+2ν7) | |
a1 | 3 | C≡C str | 2142 | A | 2142.2 M | gas | 2142 VS p | liq. | ||
a1 | 4 | CH3 s-deform | 1382 | D | 1382 S dp | liq. | ||||
a1 | 5 | C-C str | 931 | C | 930.7 W | gas | 930 S p | gas | ||
e | 6 | CH3 d-str | 3008 | A | 3008.3 M | gas | 2971 M | liq. | ||
e | 7 | CH3 d-deform | 1452 | B | 1452 M | gas | 1448 M | liq. | ||
e | 8 | CH3 rock | 1053 | A | 1052.5 W | gas | 1035 VW | liq. | ||
e | 9 | CH bend | 633 | C | 633 S | gas | 643 S dp | liq. | ||
e | 10 | CCC bend | 328 | C | 328 W | gas | 336 VS dp | liq. | ||
Source: Shimanouchi, 1972
Notes
VS | Very strong |
S | Strong |
M | Medium |
W | Weak |
VW | Very weak |
p | Polarized |
dp | Depolarized |
FR | Fermi resonance with an overtone or a combination tone indicated in the parentheses. |
A | 0~1 cm-1 uncertainty |
B | 1~3 cm-1 uncertainty |
C | 3~6 cm-1 uncertainty |
D | 6~15 cm-1 uncertainty |
E | 15~30 cm-1 uncertainty |
References
Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), 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.
Wagman, Kilpatrick, et al., 1945
Wagman, D.D.; Kilpatrick, J.E.; Pitzer, K.S.; Rossini, F.D.,
Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes, to 1,500° K,
J. Res. NBS, 1945, 35, 467-496. [all data]
Thermodynamics Research Center, 1997
Thermodynamics Research Center,
Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]
Wagman D.D., 1945
Wagman D.D.,
Heats, equilibrium constants, and free energies of formation of the acetylene hydrocarbons through the pentynes to 1500 K,
J. Res. Nat. Bur. Stand., 1945, 35, 467-496. [all data]
Daykin P.N., 1962
Daykin P.N.,
Potential energy constants, rotational distortion constants, and thermodynamic properties of methylacetylenes,
J. Chem. Phys., 1962, 37, 1087-1094. [all data]
Kistiakowsky G.B., 1940
Kistiakowsky G.B.,
Gaseous heat capacities. II,
J. Chem. Phys., 1940, 8, 610-618. [all data]
Kistiakowsky G.B., 1940, 2
Kistiakowsky G.B.,
The low temperature gaseous heat capacities of certain C3 hydrocarbons,
J. Chem. Phys., 1940, 8, 970-977. [all data]
Maass and Wright, 1921
Maass, O.; Wright, C.H.,
SOME PHYSICAL PROPERTIES OF HYDROCARBONS CONTAINING TWO AND THREE CARBON ATOMS.,
J. Am. Chem. Soc., 1921, 43, 5, 1098-1111, https://doi.org/10.1021/ja01438a013
. [all data]
Tsonopoulos and Ambrose, 1996
Tsonopoulos, C.; Ambrose, D.,
Vapor-Liquid Critical Properties of Elements and Compounds. 6. Unsaturated Aliphatic Hydrocarbons,
J. Chem. Eng. Data, 1996, 41, 645-656. [all data]
Vohra, Kang, et al., 1962
Vohra, S.P.; Kang, T.L.; Kobe, K.A.; McKetta, J.J.,
P-V-T Properties of Propyne.,
J. Chem. Eng. Data, 1962, 7, 1, 150-155, https://doi.org/10.1021/je60012a044
. [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]
Reid, 1972
Reid, Robert C.,
Handbook on vapor pressure and heats of vaporization of hydrocarbons and related compounds, R. C. Wilhort and B. J. Zwolinski, Texas A Research Foundation. College Station, Texas(1971). 329 pages.$10.00,
AIChE J., 1972, 18, 6, 1278-1278, https://doi.org/10.1002/aic.690180637
. [all data]
Van Hook, 1967
Van Hook, W. Alexander,
Vapor Pressures of the Methylacetylenes, H3CCCH, H3CCCD, D3CCCH, and D3CCCD,
J. Chem. Phys., 1967, 46, 5, 1907, https://doi.org/10.1063/1.1840952
. [all data]
Booth, Burchfield, et al., 1933
Booth, Harold Simmons; Burchfield, Paul E.; Bixby, Eva May; McKelvey, J.B.,
Fluorochloroethylenes,
J. Am. Chem. Soc., 1933, 55, 6, 2231-2235, https://doi.org/10.1021/ja01333a005
. [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]
van Hook, 1967
van Hook, W.A.,
Vapor Pressures of the Methylacetylenes, H3CCCH, H3CCCD, D3CCCH, and D3CCCD,
J. Chem. Phys., 1967, 46, 5, 1907-1918, https://doi.org/10.1063/1.1840952
. [all data]
Stull, 1947
Stull, Daniel R.,
Vapor Pressure of Pure Substances. Organic and Inorganic Compounds,
Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022
. [all data]
Gal, Decouzon, et al., 2001
Gal, J.F.; Decouzon, M.; Maria, P.C.; Gonzalez, A.I.; Mo, O.; Yanez, M.; El Chaouch, S.; Guillemin, J.C.,
Acidity trends in alpha,beta-unsaturated alkanes, silanes, germanes, and stannanes,
J. Am. Chem. Soc., 2001, 123, 26, 6353-6359, https://doi.org/10.1021/ja004079j
. [all data]
Robinson, Polak, et al., 1995
Robinson, M.S.; Polak, M.L.; Bierbaum, V.M.; DePuy, C.H.; Lineberger, W.C.,
Experimental Studies of Allene, Methylacetylene, and the Propargyl Radical: Bond Dissociation Energies, Gas-Phase Acidities, and Ion-Molecule Chemistry,
J. Am. Chem. Soc., 1995, 117, 25, 6766, https://doi.org/10.1021/ja00130a017
. [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]
Conn, Kistiakowsky, et al., 1939
Conn, J.B.; Kistiakowsky, G.B.; Smith, E.A.,
Heats of organic reactions. VIII. Some further hydrogenations, including those of some acetylenes,
J. Am. Chem. Soc., 1939, 61, 1868-1876. [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]
Staley and Beauchamp, 1975
Staley, R.H.; Beauchamp, J.L.,
Intrinsic Acid - Base Properties of Molecules. Binding Energies of Li+ to pi - and n - Donor Bases,
J. Am. Chem. Soc., 1975, 97, 20, 5920, https://doi.org/10.1021/ja00853a050
. [all data]
Dzidic and Kebarle, 1970
Dzidic, I.; Kebarle, P.,
Hydration of the Alkali Ions in the Gas Phase. Enthalpies and Entropies of Reactions M+(H2O)n-1 + H2O = M+(H2O)n,
J. Phys. Chem., 1970, 74, 7, 1466, https://doi.org/10.1021/j100702a013
. [all data]
Cordes and Gunzler, 1959
Cordes, J.F.; Gunzler, H.,
Das propin/propadien-gleichgewicht,
Chem. Ber., 1959, 92, 1055-1062. [all data]
Haynes and Armentrout, 1994
Haynes, C.L.; Armentrout, P.B.,
Thermochemistry and Structures of CoC3H6+: Metallacyclic and Metal-Alkene Isomers,
Organomettalics, 1994, 13, 9, 3480, https://doi.org/10.1021/om00021a022
. [all data]
DePuy, Gronert, et al., 1989
DePuy, C.H.; Gronert, S.; Barlow, S.E.; Bierbaum, V.M.; Damrauer, R.,
The Gas Phase Acidities of the Alkanes,
J. Am. Chem. Soc., 1989, 111, 6, 1968, https://doi.org/10.1021/ja00188a003
. [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, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas Pc Critical pressure T Temperature Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Vc Critical volume ΔfH°gas Enthalpy of formation of gas at standard conditions ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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