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Neopentane

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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
Deltafgas-167.9 ± 0.63kJ/molCcbGood, 1970ALS
Deltafgas-168.5 ± 1.0kJ/molCmPilcher and Chadwick, 1967ALS
Deltafgas-166.0 ± 1.0kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Deltacgas-3514.1 ± 0.96kJ/molCmPilcher and Chadwick, 1967Corresponding «DELTA»fgas = -168.5 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
120.82 ± 0.25298.15Hossenlopp I.A., 1981GT
129.58 ± 0.26323.15
138.41 ± 0.28348.15
147.06 ± 0.29373.15
155.46 ± 0.31398.15
163.52 ± 0.32423.15
171.46 ± 0.34448.15
178.95 ± 0.36473.15
186.42 ± 0.37498.15
193.38 ± 0.39523.15

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
80.54200.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 better agreement with experimental data than the statistical thermodynamics calculation [ Pitzer K.S., 1946].; GT
111.63273.15
120.83 ± 0.25298.15
121.55300.
155.98400.
186.98500.
214.64600.
238.91700.
261.08800.
280.33900.
297.901000.
313.381100.
327.191200.
338.901300.
351.461400.
359.821500.

Condensed 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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Deltafliquid-190.3 ± 0.63kJ/molCcbGood, 1970ALS
Deltafliquid-188.2 ± 1.0kJ/molCcbProsen and Rossini, 1945ALS
Quantity Value Units Method Reference Comment
Deltacliquid-3492.4 ± 0.59kJ/molCcbGood, 1970Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -3492.2 ± 0.50 kJ/mol; Corresponding «DELTA»fliquid = -190.1 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Deltacliquid-3494.4 ± 1.0kJ/molCcbProsen and Rossini, 1945Corresponding «DELTA»fliquid = -188.2 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid216.81J/mol*KN/AEnokida, Shinoda, et al., 1969At normal boiling point.; DH
liquid218.8J/mol*KN/AAston and Messerly, 1936DH

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
153.09259.93Enokida, Shinoda, et al., 1969T = 4 to 260 K. Value is unsmoothed experimental datum.; DH
163.89278.92Aston and Messerly, 1936T = 13 to 283 K. Value is unsmoothed experimental datum.; DH

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
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis

Quantity Value Units Method Reference Comment
Tboil282.6 ± 0.5KAVGN/AAverage of 17 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus255. ± 3.KAVGN/AAverage of 8 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple256.76KN/AEnokido, Shinoda, et al., 1969Crystal phase 1 phase; Uncertainty assigned by TRC = 0.02 K; TRC
Ttriple256.77KN/AStreiff, 1964Crystal phase 1 phase; Uncertainty assigned by TRC = 0.03 K; TRC
Ttriple256.53KN/AAston and Messerly, 1936, 2Crystal phase 1 phase; Uncertainty assigned by TRC = 0.02 K; TRC
Quantity Value Units Method Reference Comment
Tc433.8 ± 0.1KN/ADaubert, 1996 
Tc433.8KN/AMajer and Svoboda, 1985 
Tc433.8KN/ADawson, Silberberg, et al., 1973Uncertainty assigned by TRC = 0.2 K; TRC
Tc433.75KN/APartington, Rowlinson, et al., 1960Uncertainty assigned by TRC = 0.1 K; Visual, THg; TRC
Tc433.75KN/ABeattie, Douslin, et al., 1951Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Pc32.0 ± 0.1barN/ADaubert, 1996 
Pc31.963barN/ADawson, Silberberg, et al., 1973Uncertainty assigned by TRC = 0.1013 bar; TRC
Pc31.99barN/ABeattie, Douslin, et al., 1951Uncertainty assigned by TRC = 0.2027 bar; TRC
Quantity Value Units Method Reference Comment
Vc0.307l/molN/ADaubert, 1996 
Vc0.304l/molN/ABeattie, Douslin, et al., 1951Uncertainty assigned by TRC = 0.004 l/mol; TRC
Quantity Value Units Method Reference Comment
rhoc3.26 ± 0.01mol/lN/ADaubert, 1996 
rhoc3.214mol/lN/ADawson, Silberberg, et al., 1973Uncertainty assigned by TRC = 0.03 mol/l; TRC
Quantity Value Units Method Reference Comment
Deltavap22.39kJ/molN/AMajer and Svoboda, 1985 
Deltavap21.8kJ/molCHossenlopp and Scott, 1981AC
Deltavap21.85kJ/molN/AReid, 1972AC
Deltavap22.4 ± 0.59kJ/molVGood, 1970ALS

Enthalpy of vaporization

DeltavapH (kJ/mol) Temperature (K) Method Reference Comment
22.74282.7N/AMajer and Svoboda, 1985 
22.753282.61N/AAston and Messerly, 1936P = 101.325 kPa; DH
24.3272.N/AHöpfner, Parekh, et al., 2010Based on data from 257. - 293. K. See also Boublik, Fried, et al., 1984.; AC
24.0283.AStephenson and Malanowski, 1987Based on data from 268. - 313. K.; AC
23.1327.AStephenson and Malanowski, 1987Based on data from 312. - 385. K.; AC
23.1397.AStephenson and Malanowski, 1987Based on data from 382. - 433. K.; AC
22.2290.N/ADas, Reed, et al., 1977AC
19.5330.N/ADas, Reed, et al., 1977AC
16.2370.N/ADas, Reed, et al., 1977AC
11.1410.N/ADas, Reed, et al., 1977AC
22.8358.N/ADawson, Silberberg, et al., 1973Based on data from 343. - 433. K. See also Boublik, Fried, et al., 1984.; AC
22.8 ± 0.1283.N/AAston and Messerly, 1936AC

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) beta Tc (K) Reference Comment
264. - 303.36.760.2813433.8Majer and Svoboda, 1985 

Entropy of vaporization

DeltavapS (J/mol*K) Temperature (K) Reference Comment
80.50282.61Aston and Messerly, 1936P; DH

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
205.7 - 293.163.28533695.152-70.679Hopfner, Parekh, et al., 1975Coefficents calculated by NIST from author's data.
268.02 - 313.203.86373950.318-36.329Osborn and Douslin, 1974Coefficents calculated by NIST from author's data.
343. - 433.4.616161478.86841.256Dawson, Silberberg, et al., 1973Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

DeltasubH (kJ/mol) Temperature (K) Method Reference Comment
28.2241.N/AStephenson and Malanowski, 1987Based on data from 223. - 256. K.; AC
23.9210.AStull, 1947Based on data from 171. - 249. K.; AC

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
3.26256.5Domalski and Hearing, 1996AC

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
18.41140.Domalski and Hearing, 1996CAL
12.69256.5

Enthalpy of phase transition

DeltaHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
2.630140.5crystaline, IIcrystaline, IChang and Westrum, 1970DH
3.096256.76crystaline, IliquidChang and Westrum, 1970DH
2.6305140. - 142.crystaline, IIcrystaline, IEnokida, Shinoda, et al., 1969DH
3.0962256.76crystaline, IliquidEnokida, Shinoda, et al., 1969DH
2.577140.0crystaline, IIcrystaline, IAston and Messerly, 1936DH
3.255256.53crystaline, IliquidAston and Messerly, 1936DH

Entropy of phase transition

DeltaStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
18.70140.5crystaline, IIcrystaline, IChang and Westrum, 1970DH
12.05256.76crystaline, IliquidChang and Westrum, 1970DH
18.70140. - 142.crystaline, II, Secondcrystaline, I, order transition, 140 to 142 KEnokida, Shinoda, et al., 1969DH
12.06256.76crystaline, IliquidEnokida, Shinoda, et al., 1969DH
18.41140.0crystaline, IIcrystaline, IAston and Messerly, 1936DH
12.68256.53crystaline, IliquidAston and Messerly, 1936DH

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:


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
MS - José A. Martinho Simões

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

C5H11- + Hydrogen cation = Neopentane

By formula: C5H11- + H+ = C5H12

Quantity Value Units Method Reference Comment
Deltar1711. ± 8.4kJ/molBranDePuy, Gronert, et al., 1989gas phase; B
Deltar1720. ± 42.kJ/molCIDTGraul and Squires, 1990gas phase; B
Quantity Value Units Method Reference Comment
Deltar1674. ± 8.8kJ/molH-TSDePuy, Gronert, et al., 1989gas phase; B

C10H22Mg (cr) + Hydrogen (g) + Bromine (l) = 2Neopentane (l) + Br2Mg (cr)

By formula: C10H22Mg (cr) + H2 (g) + Br2 (l) = 2C5H12 (l) + Br2Mg (cr)

Quantity Value Units Method Reference Comment
Deltar-669.6 ± 6.6kJ/molRSCAkkerman, Schat, et al., 1983MS

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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Gas Phase Spectrum

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IR spectrum
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Additional Data

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Owner NIST Standard Reference Data Program
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin NIST Mass Spectrometry Data Center
State gas
Instrument HP-GC/MS/IRD

This IR spectrum is from the NIST/EPA Gas-Phase Infrared Database .


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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

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Mass spectrum
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Additional Data

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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 280

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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.

Good, 1970
Good, W.D., The enthalpies of combustion and formation of the isomeric pentanes, J. Chem. Thermodyn., 1970, 2, 237-244. [all data]

Pilcher and Chadwick, 1967
Pilcher, G.; Chadwick, J.D.M., Measurements of heats of combustion by flame calorimetry. Part 4.-n-Pentane, isopentane, neopentane, Trans. Faraday Soc., 1967, 63, 2357-2361. [all data]

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]

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]

Pitzer K.S., 1946
Pitzer K.S., The entropies and related properties of branched paraffin hydrocarbons, Chem. Rev., 1946, 39, 435-447. [all data]

Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P., Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]

Enokida, Shinoda, et al., 1969
Enokida, H.; Shinoda, T.; Mashiko, Y., Thermodynamic properties of neopentane from 4K to the melting point and comparison with spectroscopic data, Bull. Chem. Soc. Japan, 1969, 42, 84-91. [all data]

Aston and Messerly, 1936
Aston, J.G.; Messerly, G.H., Heat capacities and entropies of organic compounds. II. Thermal and vapor pressure data for tetramethylmethane from 13.22°K to the boiling point. The entropy from its Raman spectrum, J. Am. Chem. Soc., 1936, 58, 2354-2361. [all data]

Enokido, Shinoda, et al., 1969
Enokido, H.; Shinoda, T.; Mashiko, Y.-I., Thermodynamic Properties of Neopentane from 4 K to the Melting Point and Comparison with Spectroscopic Data, Bull. Chem. Soc. Jpn., 1969, 42, 84. [all data]

Streiff, 1964
Streiff, A.J., , Am. Pet. Inst. Res. Proj. 58B Unpublished, 1964. [all data]

Aston and Messerly, 1936, 2
Aston, J.G.; Messerly, G.H., Heat Capacities and Entropies of Organic Compounds II. Thermal and Vapor Pressure Data for Tetramethylmethane from 13.22K to the Boiling Point. The Entropy from its Raman Spectrum, J. Am. Chem. Soc., 1936, 58, 2354. [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]

Dawson, Silberberg, et al., 1973
Dawson, Perry P.; Silberberg, I. Harold; McKetta, John J., Volumetric behavior, vapor pressures, and critical properties of neopentane, J. Chem. Eng. Data, 1973, 18, 1, 7-15, https://doi.org/10.1021/je60056a007 . [all data]

Partington, Rowlinson, et al., 1960
Partington, E.J.; Rowlinson, J.S.; Weston, J.F., The Gas-Liquid Critical Temperatures of Binary Mixtures. Part 1., Trans. Faraday Soc., 1960, 56, 479. [all data]

Beattie, Douslin, et al., 1951
Beattie, J.A.; Douslin, D.R.; Levine, S.W., The vapor pressure and critical constants of neopentane., J. Chem. Phys., 1951, 19, 948. [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]

Höpfner, Parekh, et al., 2010
Höpfner, A.; Parekh, N.; Hörner, Ch.; Abdel-Hamid, A., Der Dampfdruck-Isotopie-Effekt von deuterierten Neopentanen, Berichte der Bunsengesellschaft für physikalische Chemie, 2010, 79, 2, 216-222, https://doi.org/10.1002/bbpc.19750790217 . [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]

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]

Das, Reed, et al., 1977
Das, Tarun R.; Reed, Charles O.; Eubank, Philip T., PVT surface and thermodynamic properties of isopentane, J. Chem. Eng. Data, 1977, 22, 1, 9-15, https://doi.org/10.1021/je60072a015 . [all data]

Hopfner, Parekh, et al., 1975
Hopfner, A.; Parekh, N.; Horner, Ch.; Abdel-Hamid, A., Der Dampfdruck-Isotopie-Effekt von deuterierten Neopentanen, Ber. Bunsen-Ges. Phys. Chem., 1975, 79, 2, 216-222, https://doi.org/10.1002/bbpc.19750790217 . [all data]

Osborn and Douslin, 1974
Osborn, Ann G.; Douslin, Donald R., Vapor-pressure relations for 15 hydrocarbons, J. Chem. Eng. Data, 1974, 19, 2, 114-117, https://doi.org/10.1021/je60061a022 . [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]

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]

Chang and Westrum, 1970
Chang, E.T.; Westrum, E.F., Heat capacities and thermodynamic properties of globular molecules. XV. The binary system tetramethylmethane-tetrachloromethane, J. Phys. Chem., 1970, 74, 2528-2538. [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]

Graul and Squires, 1990
Graul, S.T.; Squires, R.R., Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions, J. Am. Chem. Soc., 1990, 112, 7, 2517, https://doi.org/10.1021/ja00163a007 . [all data]

Akkerman, Schat, et al., 1983
Akkerman, O.S.; Schat, G.; Evers, E.A.I.M.; Bickelhaupt, F., Recl. Trav. Chim. Pays-Bas, 1983, 102, 109. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), References