Butane, 2,2,3-trimethyl-
- Formula: C7H16
- Molecular weight: 100.2019
- IUPAC Standard InChIKey: ZISSAWUMDACLOM-UHFFFAOYSA-N
- CAS Registry Number: 464-06-2
- 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: Triptan; Triptane; 2,2,3-Trimethylbutane
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Henry's Law 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 | -48.96 ± 0.27 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
ΔfH°gas | -49.21 | kcal/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 32.1 kj/mol from Prosen and Rossini, 1945.; DRB |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
26.640 | 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. Results of statistical thermodynamics calculation for 2,2,3-trimethylbutane [ Scott D.W., 1953] also agree well with experimental data at low temperatures. However, the values of S and Cp at 1500 K are 15 and 33 J/mol*K below than those given by [ Scott D.W., 1974].; GT |
35.961 | 273.15 | ||
39.02 ± 0.1 | 298.15 | ||
39.250 | 300. | ||
50.870 | 400. | ||
61.200 | 500. | ||
70.201 | 600. | ||
78.000 | 700. | ||
84.900 | 800. | ||
90.999 | 900. | ||
96.300 | 1000. | ||
101.00 | 1100. | ||
105.20 | 1200. | ||
109.00 | 1300. | ||
112.00 | 1400. | ||
115.00 | 1500. |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
42.739 ± 0.043 | 328.80 | Waddington G., 1947 | GT |
45.091 ± 0.045 | 348.85 | ||
47.390 ± 0.048 | 369.20 | ||
50.920 ± 0.050 | 400.40 | ||
54.541 ± 0.055 | 434.30 | ||
57.359 ± 0.057 | 461.80 |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, Henry's Law 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 | -56.63 ± 0.27 | kcal/mol | Ccb | Prosen and Rossini, 1945 | ALS |
ΔfH°liquid | -56.8 ± 0.3 | kcal/mol | Ccb | Davies and Gilbert, 1941 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -1148.18 ± 0.12 | kcal/mol | Cm | Coops, Mulder, et al., 1946 | Reanalyzed by Cox and Pilcher, 1970, Original value = -1147.72 ± 0.07 kcal/mol; Corresponding ΔfHºliquid = -56.70 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -1148.27 ± 0.25 | kcal/mol | Ccb | Prosen and Rossini, 1945 | Corresponding ΔfHºliquid = -56.61 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°liquid | -1148.0 ± 0.3 | kcal/mol | Ccb | Davies and Gilbert, 1941 | Corresponding ΔfHºliquid = -56.91 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°liquid | 69.849 | cal/mol*K | N/A | Huffman, Gross, et al., 1961 | DH |
S°liquid | 6.479 | cal/mol*K | N/A | Huffman, Parks, et al., 1930 | Extrapolation below 90 K, 14.0 cal mol-1 K-1.; DH |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
51.030 | 298.15 | Huffman, Gross, et al., 1961 | T = 10 to 300 K.; DH |
49.81 | 293.9 | Huffman, Parks, et al., 1930 | T = 89 to 294 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
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
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 354.1 ± 0.2 | K | AVG | N/A | Average of 35 out of 37 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 248. ± 1. | K | AVG | N/A | Average of 17 out of 18 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 248.56 | K | N/A | Huffman, Gross, et al., 1961 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.07 K; solid solution assumed for impurities in extrapolation to the triple point; TRC |
Ttriple | 248.480 | K | N/A | Waddington, 1952 | Uncertainty assigned by TRC = 0.05 K; TRC |
Ttriple | 248.530 | K | N/A | Waddington, 1952 | Uncertainty assigned by TRC = 0.03 K; TRC |
Ttriple | 248.530 | K | N/A | Huffman, 1948 | Uncertainty assigned by TRC = 0.05 K; TRC |
Ttriple | 247.7 | K | N/A | Huffman, Parks, et al., 1930, 2 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 531.1 ± 0.3 | K | N/A | Daubert, 1996 | |
Tc | 531.1 | K | N/A | Majer and Svoboda, 1985 | |
Tc | 531.11 | K | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4 K; TRC |
Tc | 531.45 | 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 | 29.1 ± 0.5 | atm | N/A | Daubert, 1996 | |
Pc | 29.146 | atm | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.4000 atm; TRC |
Pc | 29.7500 | atm | N/A | Edgar and Calingaert, 1929 | Uncertainty assigned by TRC = 0.5000 atm; measured by Keys and Kleinschmidt; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.398 | l/mol | N/A | Daubert, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 2.51 ± 0.05 | mol/l | N/A | Daubert, 1996 | |
ρc | 2.51 | mol/l | N/A | McMicking and Kay, 1965 | Uncertainty assigned by TRC = 0.05 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 7.694 | kcal/mol | N/A | Majer and Svoboda, 1985 | |
ΔvapH° | 7.6 | kcal/mol | N/A | Reid, 1972 | AC |
ΔvapH° | 7.658 | kcal/mol | C | Osborne and Ginnings, 1947 | ALS |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
6.91 | 354. | N/A | Majer and Svoboda, 1985 | |
7.74 | 299. | A | Stephenson and Malanowski, 1987 | Based on data from 284. to 355. K.; AC |
7.15 | 368. | A | Stephenson and Malanowski, 1987 | Based on data from 353. to 483. K.; AC |
7.72 | 301. | N/A | Forziati, Norris, et al., 1949 | Based on data from 286. to 355. K.; AC |
7.46 ± 0.02 | 314. | C | Waddington, Todd, et al., 1947 | AC |
7.62 | 311. | EB | Smith, 1941 | Based on data from 296. to 378. K.; 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 353. | 11.18 | 0.2726 | 531.1 | 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 | Comment |
---|---|---|---|---|---|
285.70 to 354.92 | 3.9165 | 1203.362 | -46.776 | Forziati, Norris, et al., 1949, 2 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
0.53 | 247.7 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
4.694 | 121. | Domalski and Hearing, 1996 | CAL |
2.12 | 247.7 |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.5359 | 121.4 | crystaline, II | crystaline, I | Huffman, Gross, et al., 1961 | DH |
0.5681 | 121.0 | crystaline, II | crystaline, I | Huffman, Parks, et al., 1930 | Hump in heat capacity curve at about 105 K, with excess enthalpy of 243 J/mol.; DH |
0.5261 | 247.7 | crystaline, I | liquid | Huffman, Parks, et al., 1930 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
4.414 | 121.4 | crystaline, II | crystaline, I | Huffman, Gross, et al., 1961 | DH |
4.694 | 121.0 | crystaline, II | crystaline, I | Huffman, Parks, et al., 1930 | Hump; DH |
2.12 | 247.7 | crystaline, I | liquid | Huffman, Parks, et al., 1930 | DH |
Henry's Law data
Go To: Top, Gas phase thermochemistry data, 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 by: Rolf Sander
Henry's Law constant (water solution)
kH(T) = k°H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
k°H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)
k°H (mol/(kg*bar)) | d(ln(kH))/d(1/T) (K) | Method | Reference | Comment |
---|---|---|---|---|
0.00041 | Q | N/A | missing citation give several references for the Henry's law constants but don't assign them to specific species. |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law 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]
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]
Scott D.W., 1953
Scott D.W.,
Thermodynamic functions of 2,2,3-trimethylbutane,
J. Am. Chem. Soc., 1953, 75, 2006-2007. [all data]
Waddington G., 1947
Waddington G.,
An improved flow calorimeter. Experimental vapor heat capacities and heats of vaporization of n-heptane and 2,2,3-trimethylbutane,
J. Am. Chem. Soc., 1947, 69, 22-30. [all data]
Coops, Mulder, et al., 1946
Coops, J.; Mulder, D.; Dienske, J.W.; Smittenberg, J.,
The heats of combustion of a number of hydrocarbons,
Rec. Trav. Chim. Pays/Bas, 1946, 65, 128. [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]
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]
Waddington, 1952
Waddington, G.,
Personal Commun., U. S. Bur. Mines, Bartlesville, OK, March 20, 1952. [all data]
Huffman, 1948
Huffman, H.M.,
Personal Commun., U. S. Bur. Mines, Bartlesville, OK, 1948. [all data]
Huffman, Parks, et al., 1930, 2
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]
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]
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, 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]
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]
Waddington, Todd, et al., 1947
Waddington, Guy; Todd, Samuel S.; Huffman, Hugh M.,
An Improved Flow Calorimeter. Experimental Vapor Heat Capacities and Heats of Vaporization of n-Heptane and 2,2,3-Trimethylbutane 1,
J. Am. Chem. Soc., 1947, 69, 1, 22-30, https://doi.org/10.1021/ja01193a007
. [all data]
Smith, 1941
Smith, E.R.,
Boiling points of benzene, 2,2,3-trimethylbutane, 3-ethylpentane, and 2,2,4,4-tetramethylpentane within the range 100 to 1,500 millimeters of mercury,
J. RES. NATL. BUR. STAN., 1941, 26, 2, 129-17, https://doi.org/10.6028/jres.026.004
. [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, Henry's Law 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°liquid Entropy of liquid at standard conditions Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature Vc Critical volume d(ln(kH))/d(1/T) Temperature dependence parameter for Henry's Law constant k°H Henry's Law constant at 298.15K ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition 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
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