Pentane, 2,4-dimethyl-
- Formula: C7H16
- Molecular weight: 100.2019
- IUPAC Standard InChIKey: BZHMBWZPUJHVEE-UHFFFAOYSA-N
- CAS Registry Number: 108-08-7
- 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: 2,4-Dimethylpentane
- Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
Data at NIST subscription sites:
NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.
Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change 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:
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 |
---|---|---|---|---|---|
ΔfH°gas | -202.1 ± 0.96 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
ΔfH°gas | -205.1 | kJ/mol | N/A | Davies and Gilbert, 1941 | Value computed using ΔfHliquid° value of -238.0±1.0 kj/mol from Davies and Gilbert, 1941 and ΔvapH° value of 32.9 kj/mol from Prosen and Rossini, 1945.; DRB |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 396.73 | J/mol*K | N/A | Huffman H.M., 1961 | GT |
Constant pressure heat capacity of gas
Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
115.44 | 200. | Scott D.W., 1974 | Recommended 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 |
157.57 | 273.15 | ||
170.8 ± 0.4 | 298.15 | ||
171.71 | 300. | ||
220.08 | 400. | ||
261.37 | 500. | ||
296.23 | 600. | ||
326.35 | 700. | ||
352.29 | 800. | ||
374.47 | 900. | ||
394.13 | 1000. | ||
411.29 | 1100. | ||
426.35 | 1200. | ||
439.32 | 1300. | ||
451.87 | 1400. | ||
464.42 | 1500. |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change 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:
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 | -235.0 ± 0.96 | kJ/mol | Ccb | Prosen and Rossini, 1945 | ALS |
ΔfH°liquid | -238. ± 1. | kJ/mol | Ccb | Davies and Gilbert, 1941 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -4806.29 ± 0.84 | kJ/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -234.9 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -4802. ± 1. | kJ/mol | Ccb | Davies and Gilbert, 1941 | Corresponding ΔfHºliquid = -238.9 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 303.17 | J/mol*K | N/A | Huffman, Gross, et al., 1961 | DH |
S°liquid | 291.6 | J/mol*K | N/A | Huffman, Parks, et al., 1930 | Extrapolation below 90 K, 65.90 J/mol*K.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
224.22 | 298.15 | Huffman, Gross, et al., 1961 | T = 10 to 300 K.; DH |
220.9 | 294.4 | Huffman, Parks, et al., 1930 | T = 92 to 294 K. Value is unsmoothed experimental datum.; DH |
Phase change data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry 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:
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 | 353.7 ± 0.3 | K | AVG | N/A | Average of 42 out of 48 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 153. ± 3. | K | AVG | N/A | Average of 27 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 154. ± 1. | K | AVG | N/A | Average of 7 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 519.8 ± 0.5 | K | N/A | Daubert, 1996 | |
Tc | 519.73 | K | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4 K; TRC |
Tc | 521.7 | K | N/A | Francis, 1957 | Uncertainty assigned by TRC = 2. K; TRC |
Tc | 520.25 | K | N/A | Edgar and Calingaert, 1929 | Uncertainty assigned by TRC = 0.5 K; measured by Keys and Kleinschmidt; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 27.4 ± 0.5 | bar | N/A | Daubert, 1996 | |
Pc | 27.367 | bar | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4053 bar; TRC |
Pc | 27.763 | bar | N/A | Edgar and Calingaert, 1929 | Uncertainty assigned by TRC = 0.5066 bar; measured by Keys and Kleinschmidt; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.418 | l/mol | N/A | Daubert, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 2.40 ± 0.05 | mol/l | N/A | Daubert, 1996 | |
ρc | 2.40 | mol/l | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.05 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 33.02 | kJ/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 32.7 ± 0.1 | kJ/mol | C | Svoboda, 1998 | AC |
ΔvapH° | 32.9 ± 0.1 | kJ/mol | C | Osborne and Ginnings, 1947 | AC |
ΔvapH° | 32.88 | kJ/mol | C | Osborne and Ginnings, 1947, 2 | ALS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
29.55 | 353.7 | N/A | Majer and Svoboda, 1985 | |
32.3 ± 0.1 | 308. | C | Svoboda, 1998 | AC |
31.9 ± 0.1 | 315. | C | Svoboda, 1998 | AC |
31.5 ± 0.1 | 323. | C | Svoboda, 1998 | AC |
31.0 ± 0.1 | 330. | C | Svoboda, 1998 | AC |
30.6 ± 0.1 | 338. | C | Svoboda, 1998 | AC |
30.0 ± 0.1 | 348. | C | Svoboda, 1998 | AC |
33.3 | 299. | A | Stephenson and Malanowski, 1987 | Based on data from 284. to 355. K. See also Kkykj and Repas, 1973.; AC |
33.2 | 302. | N/A | Forziati, Norris, et al., 1949 | Based on data from 287. to 354. K.; 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 |
---|---|---|---|---|---|
286.86 to 354.52 | 3.9612 | 1197.608 | -50.877 | Forziati, Norris, et al., 1949, 2 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
6.845 | 153.97 | Huffman, Gross, et al., 1961 | DH |
6.85 | 154. | Domalski and Hearing, 1996 | AC |
6.694 | 152.5 | Huffman, Parks, et al., 1930 | DH |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
44.46 | 153.97 | Huffman, Gross, et al., 1961 | DH |
43.90 | 152.5 | Huffman, Parks, et al., 1930 | DH |
References
Go To: Top, Gas phase thermochemistry data, Condensed 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]
Huffman H.M., 1961
Huffman H.M.,
Low temperature thermodynamic properties of six isomeric heptanes,
J. Phys. Chem., 1961, 65, 495-503. [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]
Huffman, Gross, et al., 1961
Huffman, H.M.; Gross, M.E.; Scott, D.W.; McCullough, I.P.,
Low temperature thermodynamic properties of six isomeric heptanes,
J. Phys. Chem., 1961, 65, 495-503. [all data]
Huffman, Parks, et al., 1930
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]
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]
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]
Francis, 1957
Francis, A.W.,
Pressure-Temperature-Liquid Density Relations of Pure Hydrocarbons,
Ind. Eng. Chem., 1957, 49, 1779. [all data]
Edgar and Calingaert, 1929
Edgar, G.; Calingaert, G.,
Preparation and Properties of the Isomeric Heptanes II. Physical Prop. properties,
J. Am. Chem. Soc., 1929, 51, 1540. [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]
Svoboda, 1998
Svoboda, V.,
Enthalpies of vaporization, and the cohesive and internal energies of 2,2-dimethylpentane, 2,4-dimethylpentane, 2,2,3-trimethylpentane, 2,3,3-trimethylpentane, and 3-ethylpentane,
The Journal of Chemical Thermodynamics, 1998, 30, 11, 1411-1417, https://doi.org/10.1006/jcht.1998.0414
. [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]
Kkykj and Repas, 1973
Kkykj, J.; Repas, M.,
Petrochemia, 1973, 13, 179. [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]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas Cp,liquid Constant pressure heat capacity of liquid Pc Critical pressure S°gas Entropy of gas at standard conditions 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°gas Enthalpy of formation of gas 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
- The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
- Customer support for NIST Standard Reference Data products.