Pentane, 2,2-dimethyl-
- Formula: C7H16
- Molecular weight: 100.2019
- IUPAC Standard InChIKey: CXOWYJMDMMMMJO-UHFFFAOYSA-N
- CAS Registry Number: 590-35-2
- 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: 2,2-Dimethylpentane
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Phase change data
Go To: Top, 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 | 352.3 ± 0.3 | K | AVG | N/A | Average of 48 out of 53 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 149. ± 2. | K | AVG | N/A | Average of 20 out of 22 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 149.2 ± 0.9 | K | AVG | N/A | Average of 7 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 520.5 ± 0.5 | K | N/A | Daubert, 1996 | |
Tc | 520.44 | K | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4 K; TRC |
Tc | 520.85 | 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 | 27.7 ± 0.5 | bar | N/A | Daubert, 1996 | |
Pc | 27.730 | bar | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4053 bar; TRC |
Pc | 28.7763 | 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 | 0.416 | l/mol | N/A | Daubert, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 2.41 ± 0.05 | mol/l | N/A | Daubert, 1996 | |
ρc | 2.41 | mol/l | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.05 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 32.56 | kJ/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 32.4 ± 0.1 | kJ/mol | C | Svoboda, 1998 | AC |
ΔvapH° | 32.4 ± 0.1 | kJ/mol | C | Osborne and Ginnings, 1947 | AC |
ΔvapH° | 32.2 ± 0.1 | kJ/mol | C | Osborne and Ginnings, 1947 | AC |
ΔvapH° | 32.42 | kJ/mol | C | Osborne and Ginnings, 1947, 2 | ALS |
Reduced pressure boiling point
Tboil (K) | Pressure (bar) | Reference | Comment |
---|---|---|---|
351.2 | 0.991 | Aldrich Chemical Company Inc., 1990 | BS |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
29.23 | 352.4 | N/A | Majer and Svoboda, 1985 | |
31.8 ± 0.1 | 308. | C | Svoboda, 1998 | AC |
31.4 ± 0.1 | 315. | C | Svoboda, 1998 | AC |
31.0 ± 0.1 | 323. | C | Svoboda, 1998 | AC |
30.5 ± 0.1 | 330. | C | Svoboda, 1998 | AC |
30.1 ± 0.1 | 338. | C | Svoboda, 1998 | AC |
29.4 ± 0.1 | 348. | C | Svoboda, 1998 | AC |
28.8 ± 0.1 | 358. | C | Svoboda, 1998 | AC |
28.1 ± 0.1 | 368. | C | Svoboda, 1998 | AC |
33.2 | 292. | A | Stephenson and Malanowski, 1987 | Based on data from 277. to 354. K.; AC |
30.1 | 368. | A | Stephenson and Malanowski, 1987 | Based on data from 353. to 483. K.; AC |
32.8 | 300. | N/A | Forziati, Norris, et al., 1949 | Based on data from 285. to 353. K.; AC |
32.6 | 303. | MM | Willingham, Taylor, et al., 1945 | Based on data from 288. to 353. 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 |
---|---|---|---|---|
288.47 to 353.20 | 3.93999 | 1190.298 | -49.807 | Williamham, Taylor, et al., 1945 |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
5.824 | 149.43 | Huffman, Gross, et al., 1961 | DH |
5.86 | 148.1 | Acree, 1991 | AC |
5.862 | 148.1 | Huffman, Parks, et al., 1930 | DH |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
38.98 | 149.43 | Huffman, Gross, et al., 1961 | DH |
39.58 | 148.1 | Huffman, Parks, et al., 1930 | DH |
References
Go To: Top, Phase change data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
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]
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [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]
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]
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]
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]
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]
Acree, 1991
Acree, William E.,
Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation,
Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H
. [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]
Notes
Go To: Top, Phase change data, References
- Symbols used in this document:
Pc Critical pressure Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Vc Critical volume 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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