Cyclopentane, methyl-
- Formula: C6H12
- Molecular weight: 84.1595
- IUPAC Standard InChIKey: GDOPTJXRTPNYNR-UHFFFAOYSA-N
- CAS Registry Number: 96-37-7
- 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. - Other names: Methylcyclopentane; UN 2298
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Condensed phase thermochemistry data
Go To: Top, Phase change data, Gas phase ion energetics 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 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 |
---|---|---|---|---|---|
ΔfH°liquid | -32.92 ± 0.17 | kcal/mol | Ccb | Good and Smith, 1969 | ALS |
ΔfH°liquid | -33.08 ± 0.20 | kcal/mol | Ccb | Prosen, Johnson, et al., 1946 | ALS |
ΔfH°liquid | -33.42 ± 0.41 | kcal/mol | Ccb | Moore, Renquist, et al., 1940 | Reanalyzed by Cox and Pilcher, 1970, Original value = -33.73 kcal/mol; see Moore and Parks, 1939; ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -941.28 ± 0.14 | kcal/mol | Ccb | Good and Smith, 1969 | Corresponding ΔfHºliquid = -32.92 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -941.14 ± 0.18 | kcal/mol | Ccb | Prosen, Johnson, et al., 1946 | Corresponding ΔfHºliquid = -33.06 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -940.78 ± 0.40 | kcal/mol | Ccb | Moore, Renquist, et al., 1940 | Reanalyzed by Cox and Pilcher, 1970, Original value = -940.36 ± 0.40 kcal/mol; see Moore and Parks, 1939; Corresponding ΔfHºliquid = -33.42 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -945.6 | kcal/mol | Ccb | Zubova, 1901 | Corresponding ΔfHºliquid = -28.6 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 59.221 | cal/mol*K | N/A | Douslin and Huffman, 1946 | DH |
S°liquid | 59.20 | cal/mol*K | N/A | Huffman, Parks, et al., 1931 | Extrapolation below 90 K, 57.86 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
37.682 | 293.15 | Siddiqi, Svejda, et al., 1983 | DH |
38.031 | 299.8 | Connolly, Sage, et al., 1951 | T = 80 to 200°F.; DH |
37.930 | 298.15 | Douslin and Huffman, 1946 | T = 12 to 300 K.; DH |
37.60 | 295.7 | Huffman, Parks, et al., 1931 | T = 92 to 294 K. Value is unsmoothed experimental datum.; DH |
Phase change data
Go To: Top, Condensed phase thermochemistry data, Gas phase ion energetics 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 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
DRB - Donald R. Burgess, Jr.
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 345.0 ± 0.2 | K | AVG | N/A | Average of 35 out of 41 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 131. ± 1. | K | AVG | N/A | Average of 30 out of 35 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 130.5 ± 0.6 | K | AVG | N/A | Average of 6 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 532.7 ± 0.2 | K | N/A | Daubert, 1996 | |
Tc | 532.7 | K | N/A | Majer and Svoboda, 1985 | |
Tc | 532.73 | K | N/A | Kudchadker, Alani, et al., 1968 | Uncertainty assigned by TRC = 0.3 K; TRC |
Tc | 532.7 | K | N/A | Ambrose, Cox, et al., 1960 | Uncertainty assigned by TRC = 0.2 K; Vis, PRT, IPTS-48; TRC |
Tc | 532.76 | K | N/A | Kay, 1947 | Uncertainty assigned by TRC = 0.05 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 37.4 ± 0.4 | atm | N/A | Daubert, 1996 | |
Pc | 37.35 | atm | N/A | Kudchadker, Alani, et al., 1968 | Uncertainty assigned by TRC = 0.4000 atm; TRC |
Pc | 37.3640 | atm | N/A | Kay, 1947 | Uncertainty assigned by TRC = 0.0499 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.318 | l/mol | N/A | Daubert, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 3.14 ± 0.04 | mol/l | N/A | Daubert, 1996 | |
ρc | 3.137 | mol/l | N/A | Kudchadker, Alani, et al., 1968 | Uncertainty assigned by TRC = 0.05 mol/l; TRC |
ρc | 3.14 | mol/l | N/A | Kay, 1947 | Uncertainty assigned by TRC = 0.02 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 7.57 ± 0.03 | kcal/mol | AVG | N/A | Average of 6 values; Individual data points |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
6.950 | 345. | N/A | Majer and Svoboda, 1985 | |
7.50 | 315. | N/A | Sapei, Uusi-Kyyny, et al., 2010 | Based on data from 300. to 345. K.; AC |
7.62 | 303. | A,MM | Stephenson and Malanowski, 1987 | Based on data from 288. to 346. K. See also Willingham, Taylor, et al., 1945.; AC |
7.487 ± 0.004 | 304. | V | McCullough, Pennington, et al., 1959 | ALS |
7.48 ± 0.02 | 304. | C | McCullough, Pennington, et al., 1959 | AC |
7.22 ± 0.02 | 326. | C | McCullough, Pennington, et al., 1959 | AC |
6.96 ± 0.02 | 345. | C | McCullough, Pennington, et al., 1959 | AC |
Enthalpy of vaporization
ΔvapH =
A exp(-βTr) (1 − Tr)β
ΔvapH =
Enthalpy of vaporization (at saturation pressure)
(kcal/mol)
Tr = reduced temperature (T / Tc)
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Temperature (K) | A (kcal/mol) | β | Tc (K) | Reference | Comment |
---|---|---|---|---|---|
298. to 345. | 10.99 | 0.271 | 532.7 | Majer and Svoboda, 1985 |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)
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Temperature (K) | A | B | C | Reference |
---|---|---|---|---|
288.18 to 345.78 | 3.98202 | 1186.059 | -47.108 | Williamham, Taylor, et al., 1945 |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.6560 | 130.73 | Douslin and Huffman, 1946 | DH |
1.66 | 130.7 | Domalski and Hearing, 1996 | AC |
1.645 | 130.1 | Huffman, Parks, et al., 1931 | DH |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
12.67 | 130.73 | Douslin and Huffman, 1946 | DH |
12.6 | 130.1 | Huffman, Parks, et al., 1931 | DH |
Gas phase ion energetics data
Go To: Top, Condensed phase thermochemistry data, Phase change 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 evaluated as indicated in comments:
L - Sharon G. Lias
Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
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 C6H12+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.7 ± 0.1 | eV | N/A | N/A | L |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.62 ± 0.05 | EI | Holmes and Lossing, 1991 | LL |
9.85 | EQ | Lias, Ausloos, et al., 1976 | LLK |
10.42 | EI | Lossing and Traeger, 1975 | LLK |
10.34 ± 0.04 | PE | Rang, Paldoia, et al., 1974 | LLK |
10.45 | EI | Pottie, Harrison, et al., 1961 | RDSH |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C5H9+ | 10.42 | CH3 | EI | Lossing and Traeger, 1975, 2 | LLK |
C5H9+ | 10.73 | CH3 | EI | Lossing and Traeger, 1975 | LLK |
C5H9+ | 10.95 | CH3 | EI | Pottie, Harrison, et al., 1961 | RDSH |
Mass spectrum (electron ionization)
Go To: Top, Condensed phase thermochemistry data, Phase change 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 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. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-NW-1064 |
NIST MS number | 227793 |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, 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.
Good and Smith, 1969
Good, W.D.; Smith, N.K.,
Enthalpies of combustion of toluene, benzene, cyclohexane, cyclohexene, methylcyclopentane, 1-methylcyclopentene, and n-hexane,
J. Chem. Eng. Data, 1969, 14, 102-106. [all data]
Prosen, Johnson, et al., 1946
Prosen, E.J.; Johnson, W.H.; Rossini, F.D.,
Heats of formation and combustion of the normal alkylcyclopentanes and cyclohexanes and the increment per CH2 group for several homologous series of hydrocarbons,
J. Res. NBS, 1946, 37, 51-56. [all data]
Moore, Renquist, et al., 1940
Moore, G.E.; Renquist, M.L.; Parks, G.S.,
Thermal data on organic compounds. XX. Modern combustion data for two methylnonanes, methyl ethyl ketone, thiophene and six cycloparaffins,
J. Am. Chem. Soc., 1940, 62, 1505-1507. [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]
Moore and Parks, 1939
Moore, G.E.; Parks, G.S.,
New thermodynamic data for the cyclohexane-methylcyclopentane isomerization,
J. Am. Chem. Soc., 1939, 61, 2561-2562. [all data]
Zubova, 1901
Zubova, P.,
Data about heat of combustion of compound cycle structure,
Zh. Fiz. Khim., 1901, 33, 708-722. [all data]
Douslin and Huffman, 1946
Douslin, D.R.; Huffman, H.M.,
The heat capacities, heats of transition, heats of fusion and entropies of cyclopentane, methylcyclopentane and methylcylohexane,
J. Am. Chem. Soc., 1946, 68, 173-176. [all data]
Huffman, Parks, et al., 1931
Huffman, H.M.; Parks, G.S.; Barmore, M.,
Thermal data on organic compounds. X. Further studies on the heat capacities, entropies and free energies of hydrocarbons,
J. Am. Chem. Soc., 1931, 53, 3876-3888. [all data]
Siddiqi, Svejda, et al., 1983
Siddiqi, M.A.; Svejda, P.; Kohler, F.,
A generalized van der Waals equation of state II. Excess heat capacities of mixtures containing cycloalkanes (C5,C6), methylcycloalkanes (C5,C6) and n-decane,
Ber. Bunsenges. Phys. Chem., 1983, 87, 1176-1181. [all data]
Connolly, Sage, et al., 1951
Connolly, T.J.; Sage, B.H.; Lacey, W.N.,
Isobaric heat capacities at bubble point. n-Hexane, methylcyclopentane, and n-octane,
Ind. Eng. Chem., 1951, 43, 946-950. [all data]
Daubert, 1996
Daubert, T.E.,
Vapor-Liquid Critical Properties of Elements and Compounds. 5. Branched Alkanes and Cycloalkanes,
J. Chem. Eng. Data, 1996, 41, 365-372. [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]
Kudchadker, Alani, et al., 1968
Kudchadker, A.P.; Alani, G.H.; Zwolinski, B.J.,
The Critical Constants of Organic Substances,
Chem. Rev., 1968, 68, 659. [all data]
Ambrose, Cox, et al., 1960
Ambrose, D.; Cox, J.D.; Townsend, R.,
The critical temperatures of forty organic compounds,
Trans. Faraday Soc., 1960, 56, 1452. [all data]
Kay, 1947
Kay, W.B.,
Vapor Pressures and Saturated Liquid and Vapor DEensities of Cyclopentane, Methylcyclopentane, Ethylcyclopentane, and Methylcyclohexane,
J. Am. Chem. Soc., 1947, 69, 1273-7. [all data]
Sapei, Uusi-Kyyny, et al., 2010
Sapei, Erlin; Uusi-Kyyny, Petri; Keskinen, Kari I.; Alopaeus, Ville,
Phase equilibria of binary systems of 3-methylthiophene with four different hydrocarbons,
Fluid Phase Equilibria, 2010, 288, 1-2, 155-160, https://doi.org/10.1016/j.fluid.2009.11.004
. [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]
Willingham, Taylor, et al., 1945
Willingham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D.,
Vapor pressures and boiling points of some paraffin, alkylcyclopentane, alkylcyclohexane, and alkylbenzene hydrocarbons,
J. RES. NATL. BUR. STAN., 1945, 35, 3, 219-17, https://doi.org/10.6028/jres.035.009
. [all data]
McCullough, Pennington, et al., 1959
McCullough, J.P.; Pennington, R.E.; Smith, J.C.; Hossenlopp, I.A.; Waddington, G.,
Thermodynamics of cyclopentane, methylcyclopentane and 1,cis-3-dimethylcyclopentane: Verification of the concept of pseudorotation,
J. Am. Chem. Soc., 1959, 81, 5880-5883. [all data]
Williamham, Taylor, et al., 1945
Williamham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D.,
Vapor Pressures and Boiling Points of Some Paraffin, Alkylcyclopentane, Alkylcyclohexane, and Alkylbenzene Hydrocarbons,
J. Res. Natl. Bur. Stand. (U.S.), 1945, 35, 3, 219-244, https://doi.org/10.6028/jres.035.009
. [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]
Holmes and Lossing, 1991
Holmes, J.L.; Lossing, F.P.,
Ionization energies of homologous organic compounds and correlation with molecular size,
Org. Mass Spectrom., 1991, 26, 537. [all data]
Lias, Ausloos, et al., 1976
Lias, S.G.; Ausloos, P.; Horvath, Z.,
Charge transfer reactions in alkane and cycloalkane systems. Estimated ionization potentials,
Int. J. Chem. Kinet., 1976, 8, 725. [all data]
Lossing and Traeger, 1975
Lossing, F.P.; Traeger, J.C.,
Stabilization in cyclopentadienyl, cyclopentenyl, and cyclopentyl cations,
J. Am. Chem. Soc., 1975, 97, 1579. [all data]
Rang, Paldoia, et al., 1974
Rang, S.; Paldoia, P.; Talvari, A.,
Ionization potentials of unsaturated hydrocarbons. 2. Mono-substituted cyclopentenes and cyclohexenes,
Eesti. NSV Tead. Akad. Toim., 1974, 354. [all data]
Pottie, Harrison, et al., 1961
Pottie, R.F.; Harrison, A.G.; Lossing, F.P.,
Free radicals by mass spectrometry. XXIV. Ionization potentials of cycloalkyl free radicals and cycloalkanes,
J. Am. Chem. Soc., 1961, 83, 3204. [all data]
Lossing and Traeger, 1975, 2
Lossing, F.P.; Traeger, J.C.,
Free radicals by mass spectrometry XLVI. Heats of formation of C5H7 and C5H9 radicals and cations.,
J. Am. Chem. Soc., 1975, 19, 9. [all data]
Notes
Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), References
- Symbols used in this document:
AE Appearance energy Cp,liquid Constant pressure heat capacity of liquid IE (evaluated) Recommended ionization energy Pc Critical pressure S°liquid Entropy of liquid at standard conditions Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Vc Critical volume ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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