Pentane, 3,3-dimethyl-

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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
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas-201.5 ± 0.92kJ/molCcbProsen and Rossini, 1945ALS
Δfgas-205.9kJ/molN/ADavies and Gilbert, 1941Value computed using ΔfHliquid° value of -239.0±1.0 kj/mol from Davies and Gilbert, 1941 and ΔvapH° value of 33.1 kj/mol from Prosen and Rossini, 1945.; DRB
Quantity Value Units Method Reference Comment
gas398.02J/mol*KN/AFinke H.L., 1976GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
187.44 ± 0.37344.13Hossenlopp I.A., 1981GT
197.68 ± 0.40366.22
214.51 ± 0.43402.31
235.08 ± 0.47449.30
250.70 ± 0.50487.21

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
113.72200.Scott D.W., 1974Recommended values were obtained from the consistent correlation scheme for alkanes [ Scott D.W., 1974, 2, Scott D.W., 1974]. This approach gives a good agreement with experimental data available for alkanes. However, large uncertainties could be expected at high temperatures.; GT
152.97273.15
165.8 ± 0.8298.15
166.69300.
215.35400.
258.45500.
295.81600.
327.61700.
355.22800.
379.49900.
400.411000.
419.241100.
435.551200.
451.871300.
464.421400.
476.981500.

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
Tboil359.2 ± 0.2KAVGN/AAverage of 34 out of 38 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus138.1 ± 0.9KAVGN/AAverage of 25 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple138.75KN/AFinke, Messerly, et al., 1976Crystal phase 1 phase; Uncertainty assigned by TRC = 0.1 K; TRC
Ttriple138.2KN/AFinke, Messerly, et al., 1976Crystal phase 2 phase; Uncertainty assigned by TRC = 0.03 K; C2 is metastable at the melting point; TRC
Ttriple138.2KN/AHuffman, Parks, et al., 1930Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Tc536.4 ± 0.5KN/ADaubert, 1996 
Tc536.3KN/AMajer and Svoboda, 1985 
Tc536.34KN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4 K; TRC
Quantity Value Units Method Reference Comment
Pc29.5 ± 0.5barN/ADaubert, 1996 
Pc29.458barN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.4053 bar; TRC
Quantity Value Units Method Reference Comment
Vc0.414l/molN/ADaubert, 1996 
Quantity Value Units Method Reference Comment
ρc2.42 ± 0.05mol/lN/ADaubert, 1996 
ρc2.42mol/lN/AMcMicking and Kay, 1965Uncertainty assigned by TRC = 0.05 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap33.15kJ/molN/AMajer and Svoboda, 1985 
Δvap33.0 ± 0.1kJ/molCHossenlopp and Scott, 1981AC
Δvap33.0kJ/molN/AReid, 1972AC
Δvap33.0 ± 0.1kJ/molCOsborne and Ginnings, 1947AC
Δvap33.02kJ/molCOsborne and Ginnings, 1947, 2ALS

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
29.62359.2N/AMajer and Svoboda, 1985 
34.8266.N/AStephenson and Malanowski, 1987Based on data from 213. to 281. K.; AC
33.6295.N/AStephenson and Malanowski, 1987Based on data from 280. to 360. K.; AC
33.3300.MMStephenson and Malanowski, 1987Based on data from 285. to 360. K. See also Willingham, Taylor, et al., 1945.; AC
33.2302.N/AForziati, Norris, et al., 1949Based on data from 287. to 360. K.; AC

Enthalpy of vaporization

ΔvapH = A exp(-βTr) (1 − Tr)β
    ΔvapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    Tr = reduced temperature (T / Tc)

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Temperature (K) A (kJ/mol) β Tc (K) Reference Comment
298. to 359.47.530.2661536.3Majer and Svoboda, 1985 

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
286.63 to 360.113.955681230.986-47.568Forziati, Norris, et al., 1949, 2Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
7.07138.2Domalski and Hearing, 1996AC
7.067138.2Huffman, Parks, et al., 1930, 2DH

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
51.14138.2Huffman, Parks, et al., 1930, 2DH

Enthalpy of phase transition

ΔHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
0.7937132.7crystaline, IIcrystaline, IFinke, Messerly, et al., 1976, 2DH
7.6425138.20crystaline, IIliquidFinke, Messerly, et al., 1976, 2DH
6.8463138.75crystaline, IliquidFinke, Messerly, et al., 1976, 2DH

Entropy of phase transition

ΔStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
5.98132.7crystaline, IIcrystaline, IFinke, Messerly, et al., 1976, 2DH
55.30138.20crystaline, IIliquidFinke, Messerly, et al., 1976, 2DH
49.34138.75crystaline, IliquidFinke, Messerly, et al., 1976, 2DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


References

Go To: Top, Gas phase thermochemistry data, Phase change data, Notes

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

Prosen and Rossini, 1945
Prosen, E.J.; Rossini, F.D., Heats of combustion and formation of the paraffin hydrocarbons at 25° C, J. Res. NBS, 1945, 263-267. [all data]

Davies and Gilbert, 1941
Davies, G.F.; Gilbert, E.C., Heats of combustion and formation of the nine isomeric heptanes in the liquid state, J. Am. Chem. Soc., 1941, 63, 2730-2732. [all data]

Finke H.L., 1976
Finke H.L., Low-temperature thermal quantities for five alkyl-substituted pentanes, J. Chem. Thermodyn., 1976, 8, 965-983. [all data]

Hossenlopp I.A., 1981
Hossenlopp I.A., Vapor heat capacities and enthalpies of vaporization of five alkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 415-421. [all data]

Scott D.W., 1974
Scott D.W., Chemical Thermodynamic Properties of Hydrocarbons and Related Substances. Properties of the Alkane Hydrocarbons, C1 through C10 in the Ideal Gas State from 0 to 1500 K. U.S. Bureau of Mines, Bulletin 666, 1974. [all data]

Scott D.W., 1974, 2
Scott D.W., Correlation of the chemical thermodynamic properties of alkane hydrocarbons, J. Chem. Phys., 1974, 60, 3144-3165. [all data]

Finke, Messerly, et al., 1976
Finke, H.L.; Messerly, J.F.; Douslin, D.R., Low-Temp. Thermal Quantities for Five Alkyl-Substituted Pentanes, J. Chem. Thermodyn., 1976, 8, 965. [all data]

Huffman, Parks, et al., 1930
Huffman, H.M.; Parks, G.S.; Thomas, S.B., Thermal Data on Organic Compounds. VII The Heat Capacities, Entropies and Free Energies of the Isomeric Heptanes, J. Am. Chem. Soc., 1930, 52, 3241. [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]

McMicking and Kay, 1965
McMicking, J.H.; Kay, W.B., Vapor Pressures and Saturated Liquid and Vapor Densities of The Isomeric Heptanes and Isomeric Octanes, Proc., Am. Pet. Inst., Sect. 3, 1965, 45, 75-90. [all data]

Hossenlopp and Scott, 1981
Hossenlopp, I.A.; Scott, D.W., Vapor heat capacities and enthalpies of vaporization of five alkane hydrocarbons, J. Chem. Thermodyn., 1981, 13, 415-421. [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]

Osborne and Ginnings, 1947
Osborne, Nathan S.; Ginnings, Defoe C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. RES. NATL. BUR. STAN., 1947, 39, 5, 453-17, https://doi.org/10.6028/jres.039.031 . [all data]

Osborne and Ginnings, 1947, 2
Osborne, N.S.; Ginnings, D.C., Measurements of heat of vaporization and heat capacity of a number of hydrocarbons, J. Res. NBS, 1947, 39, 453-477. [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]

Forziati, Norris, et al., 1949
Forziati, Alphonse F.; Norris, William R.; Rossini, Frederick D., Vapor pressures and boiling points of sixty API-NBS hydrocarbons, J. RES. NATL. BUR. STAN., 1949, 43, 6, 555-17, https://doi.org/10.6028/jres.043.050 . [all data]

Forziati, Norris, et al., 1949, 2
Forziati, A.F.; Norris, W.R.; Rossini, F.D., Vapor Pressures and Boiling Points of Sixty API-NBS Hydrocarbons, J. Res. Natl. Bur. Stand. (U.S.), 1949, 43, 6, 555-563, https://doi.org/10.6028/jres.043.050 . [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]

Huffman, Parks, et al., 1930, 2
Huffman, H.M.; Parks, G.S.; Thomas, S.B., Thermal data on organic compounds. VIII. The heat capacities, entropies and free energies of the isomeric heptanes, J. Am. Chem. Soc., 1930, 52, 3241-3251. [all data]

Finke, Messerly, et al., 1976, 2
Finke, H.L.; Messerly, J.F.; Douslin, D.R., Low-temperature thermal quantities for five alkyl-substituted pentanes, J. Chem. Thermodynam., 1976, 8, 965-983. [all data]


Notes

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