1-Propene, 2-methyl-
- Formula: C4H8
- Molecular weight: 56.1063
- IUPAC Standard InChIKey: VQTUBCCKSQIDNK-UHFFFAOYSA-N
- CAS Registry Number: 115-11-7
- 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: Propene, 2-methyl-; γ-Butylene; Isobutene; Isobutylene; Isopropylidenemethylene; 1,1-Dimethylethylene; 2-Methyl-1-propene; 2-Methylpropene; iso-C4H8; Methylpropene; UN 1055; 1,1-Dimethylethene; 2-Methylpropylene
- 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 / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
- NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)
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, Vibrational and/or electronic energy levels, 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -4.29 ± 0.26 | kcal/mol | Cm | Prosen, Maron, et al., 1951 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°gas | -645.19 ± 0.25 | kcal/mol | Cm | Prosen, Maron, et al., 1951 | Corresponding ΔfHºgas = -4.27 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
ΔcH°gas | -650.6 | kcal/mol | Ccb | Guinchant, 1918 | Corresponding ΔfHºgas = 1.1 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas | 70.170 | cal/mol*K | N/A | Stull D.R., 1969 | This value was obtained on the basis of calorimetric data [ Todd S.S., 1936]. Experimental value of S(298 K)=288.7 J/mol*K [ Todd S.S., 1936] could not be recommended because of its large uncertainty.; GT |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
8.528 | 50. | Thermodynamics Research Center, 1997 | p=1 bar. Recommended values are in close agreement with other statistically calculated values [ Kilpatrick J.E., 1946] as well as with ab initio value of S(298.15 K)=293.37 J/mol*K [ East A.L.L., 1997].; GT |
10.98 | 100. | ||
13.58 | 150. | ||
16.09 | 200. | ||
19.77 | 273.15 | ||
21.05 | 298.15 | ||
21.15 | 300. | ||
26.240 | 400. | ||
30.915 | 500. | ||
35.010 | 600. | ||
38.564 | 700. | ||
41.659 | 800. | ||
44.357 | 900. | ||
46.714 | 1000. | ||
48.764 | 1100. | ||
50.550 | 1200. | ||
52.101 | 1300. | ||
53.454 | 1400. | ||
54.632 | 1500. | ||
56.977 | 1750. | ||
58.678 | 2000. | ||
59.940 | 2250. | ||
60.894 | 2500. | ||
61.623 | 2750. | ||
62.189 | 3000. |
Constant pressure heat capacity of gas
Cp,gas (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
18.13 ± 0.091 | 239.15 | Scott R.B., 1945 | GT |
19.81 ± 0.098 | 272.15 | ||
21.91 ± 0.11 | 312.15 | ||
23.96 ± 0.12 | 353.15 |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Phase change data, Vibrational and/or electronic energy levels, 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: Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
S°liquid | 46.4 | cal/mol*K | N/A | Todd and Parks, 1936 | Extrapolation below 90 K, 45.23 J/mol*K. |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
28.99 | 266.26 | Rabinovich and Lebedev, 1971 | T = 90 to 266 K. |
29.020 | 253.1 | Todd and Parks, 1936 | T = 93.3 to 253 K. Value is unsmoothed experimental datum. |
Phase change data
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Vibrational and/or electronic energy levels, 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:
DH - Eugene S. Domalski and Elizabeth D. Hearing
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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 266.7 ± 0.7 | K | AVG | N/A | Average of 25 out of 28 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 132.38 | K | N/A | Rabinovich and Lebedev, 1971 | DH |
Tfus | 132.45 | K | N/A | Kistiakowsky, Ruhoff, et al., 1935 | Uncertainty assigned by TRC = 0.3 K; TRC |
Tfus | 125.4 | K | N/A | Coffin and Maass, 1928 | Uncertainty assigned by TRC = 0.5 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 132.4 | K | N/A | Todd and Parks, 1936, 2 | Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 417.9 ± 0.1 | K | N/A | Tsonopoulos and Ambrose, 1996 | |
Tc | 417.88 | K | N/A | Beattie, Ingersoll, et al., 1942 | Uncertainty assigned by TRC = 0.1 K; TRC |
Tc | 420.15 | K | N/A | Coffin and Maass, 1928 | Uncertainty assigned by TRC = 2. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 39.48 ± 0.099 | atm | N/A | Tsonopoulos and Ambrose, 1996 | |
Pc | 39.4800 | atm | N/A | Beattie, Ingersoll, et al., 1942 | Uncertainty assigned by TRC = 0.09998 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.2388 | l/mol | N/A | Tsonopoulos and Ambrose, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 4.19 ± 0.010 | mol/l | N/A | Tsonopoulos and Ambrose, 1996 | |
ρc | 4.17 | mol/l | N/A | Beattie, Ingersoll, et al., 1942 | Uncertainty assigned by TRC = 0.05 mol/l; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 4.92 | kcal/mol | N/A | Reid, 1972 | AC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
5.52 | 264. | A | Stephenson and Malanowski, 1987 | Based on data from 212. to 279. K.; AC |
5.43 | 281. | A | Stephenson and Malanowski, 1987 | Based on data from 266. to 313. K.; AC |
5.31 | 325. | A | Stephenson and Malanowski, 1987 | Based on data from 310. to 376. K.; AC |
5.33 | 386. | A | Stephenson and Malanowski, 1987 | Based on data from 371. to 418. K.; AC |
5.31 | 350. | N/A | Beattie, Ingersoll, et al., 1942, 2 | Based on data from 303. to 398. K.; AC |
5.45 | 258. | N/A | Lamb and Roper, 1940 | Based on data from 216. to 273. K. See also Boublik, Fried, et al., 1984.; AC |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
216.40 to 273. | 3.64138 | 799.055 | -46.615 | Lamb and Roper, 1940 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.41 | 132.4 | Domalski and Hearing, 1996 | AC |
1.415 | 132.4 | Todd and Parks, 1936 | DH |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
10.69 | 132.4 | Todd and Parks, 1936 | DH |
Vibrational and/or electronic energy levels
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: Takehiko Shimanouchi
Symmetry: C2ν Symmetry Number σ = 2
Sym. | No | Approximate | Selected Freq. | Infrared | Raman | Comments | ||||
---|---|---|---|---|---|---|---|---|---|---|
Species | type of mode | Value | Rating | Value | Phase | Value | Phase | |||
a1 | 1 | CH2 s-str | 2989 | D | 2991 M | sln. | 2989 S p | liq. | ||
a1 | 2 | CH3 d-str | 2941 | C | 2940.8 | gas | 2930 W p | liq. | ||
a1 | 3 | CH3 s-str | 2911 | D | 2919 W | gas | 2911 S p | liq. | ||
a1 | 4 | C=C str | 1661 | C | 1661.1 S | gas | 1655 S p | liq. | ||
a1 | 5 | CH3 d-deform | 1470 | C | 1469.6 S | gas | 1462 VW | liq. | ||
a1 | 6 | CH2 scis | 1416 | D | 1419 W | sln. | 1416 S p | liq. | ||
a1 | 7 | CH3 s-deform | 1366 | D | 1366 VW p | liq. | ||||
a1 | 8 | CH3 rock | 1064 | C | 1063.9 S | gas | 1058 W p | liq. | ||
a1 | 9 | C-C str | 801 | C | 801 W | gas | 803 VS p | liq. | ||
a1 | 10 | C=CC2 ip-deform | 383 | D | 384 W | sln. | 383 W | liq. | ||
a2 | 11 | CH3 d-str | 2970 | D | ia | 2970 W p | liq. | OV(ν17) | ||
a2 | 12 | CH3 d-deform | 1459 | D | ia | 1459 VW | liq. | |||
a2 | 13 | CH3 rock | 1076 | E | ia | CF | ||||
a2 | 14 | CH2 twist | 981 | E | ia | CF | ||||
a2 | 15 | CH3 torsion | 193 | E | ia | CF | ||||
b1 | 16 | CH2 a-str | 3086 | C | 3086.0 S | gas | 3079 W dp | liq. | ||
b1 | 17 | CH3 d-str | 2980 | C | 2980.4 | gas | 2970 W dp | liq. | OV(ν11) | |
b1 | 18 | CH3 s-str | 2893 | C | 2892.9 W | gas | 2892 W dp | liq. | ||
b1 | 19 | CH3 d-deform | 1458 | C | 1458.4 S | gas | ||||
b1 | 20 | CH3 s-deform | 1381 | C | 1381.2 S | gas | 1386 W | liq. | ||
b1 | 21 | C-C str | 1282 | C | 1281.9 S | gas | 1281 W | liq. | ||
b1 | 22 | CH3 rock | 1043 | E | CF | |||||
b1 | 23 | CH2 rock | 974 | C | 973.7 W | gas | 972 VW | liq. | ||
b1 | 24 | C=CC2 ip-deform | 430 | D | 430 sh | sln. | ||||
b2 | 25 | CH3 d-str | 2945 | C | 2944.9 S | gas | ||||
b2 | 26 | CH3 d-deform | 1444 | C | 1443.7 S | gas | 1439 VW | liq. | ||
b2 | 27 | CH3 rock | 1079 | C | 1079.0 S | gas | ||||
b2 | 28 | CH2 wag | 890 | C | 889.7 VS | gas | 883 W dp | liq. | ||
b2 | 29 | C=CC2 op-deform | 429 | C | 429.1 S | gas | 431 W dp | liq. | ||
b2 | 30 | CH3 torsion | 196 | C | 196 VW | gas | ||||
Source: Shimanouchi, 1972
Notes
VS | Very strong |
S | Strong |
M | Medium |
W | Weak |
VW | Very weak |
ia | Inactive |
sh | Shoulder |
p | Polarized |
dp | Depolarized |
CF | Calculated frequency |
OV | Overlapped by band indicated in parentheses. |
C | 3~6 cm-1 uncertainty |
D | 6~15 cm-1 uncertainty |
E | 15~30 cm-1 uncertainty |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Vibrational and/or electronic energy levels, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Prosen, Maron, et al., 1951
Prosen, E.J.; Maron, F.W.; Rossini, F.D.,
Heats of combustion, formation, and insomerization of ten C4 hydrocarbons,
J. Res. NBS, 1951, 46, 106-112. [all data]
Guinchant, 1918
Guinchant, M.J.,
Etude sur la fonction acide dans les derives metheniques et methiniques,
Ann. Chem., 1918, 10, 30-84. [all data]
Stull D.R., 1969
Stull D.R., Jr.,
The Chemical Thermodynamics of Organic Compounds. Wiley, New York, 1969. [all data]
Todd S.S., 1936
Todd S.S.,
Thermal data on organic compounds. XV. Some heat capacity, entropy and free energy data for the isomeric butenes,
J. Am. Chem. Soc., 1936, 58, 134-137. [all data]
Thermodynamics Research Center, 1997
Thermodynamics Research Center,
Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]
Kilpatrick J.E., 1946
Kilpatrick J.E.,
Heat content, free energy function, entropy, and heat capacity of ethylene, propylene, and the four butenes to 1500 K,
J. Res. Nat. Bur. Stand, 1946, 37, 163-171. [all data]
East A.L.L., 1997
East A.L.L.,
Ab initio statistical thermodynamical models for the computation of third-law entropies,
J. Chem. Phys., 1997, 106, 6655-6674. [all data]
Scott R.B., 1945
Scott R.B.,
Specific heats of gaseous 1,3-butadiene, isobutene, styrene, and ethylbenzene,
J. Res. Nat. Bur. Stand., 1945, 34, 243-254. [all data]
Todd and Parks, 1936
Todd, S.S.; Parks, G.S.,
Thermal data on organic compounds. XV. Some heat capacity, entropy and free energy data for the isomeric butenes,
J. Am. Chem. Soc., 1936, 58, 134-137. [all data]
Rabinovich and Lebedev, 1971
Rabinovich, I.B.; Lebedev, B.V.,
On the thermodynamic stability of polyisobutylene. Tr. Khim. Khim. Tekhnol., 1971, 194-196. [all data]
Kistiakowsky, Ruhoff, et al., 1935
Kistiakowsky, G.B.; Ruhoff, J.R.; Smith, H.A.; Vaughan, W.E.,
Heats of Organic Reactions II. Hydrogenation of Some Simpler Olefinic Hydrocarbons,
J. Am. Chem. Soc., 1935, 57, 876-82. [all data]
Coffin and Maass, 1928
Coffin, C.C.; Maass, O.,
The Preparation and Physical Properties of α-,β- and γ-Butylene and Normal and Isobutane,
J. Am. Chem. Soc., 1928, 50, 1427-37. [all data]
Todd and Parks, 1936, 2
Todd, S.S.; Parks, G.S.,
Thermal Data on Organic Compounds XV. Some Heat Capacity, Entropy and Free Energy Data for the Isomeric Butenes,
J. Am. Chem. Soc., 1936, 58, 134. [all data]
Tsonopoulos and Ambrose, 1996
Tsonopoulos, C.; Ambrose, D.,
Vapor-Liquid Critical Properties of Elements and Compounds. 6. Unsaturated Aliphatic Hydrocarbons,
J. Chem. Eng. Data, 1996, 41, 645-656. [all data]
Beattie, Ingersoll, et al., 1942
Beattie, J.A.; Ingersoll, H.G.; Stockmayer, W.H.,
Vapor Pressure and Critical Consants of Isobutene,
J. Am. Chem. Soc., 1942, 64, 546. [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]
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]
Beattie, Ingersoll, et al., 1942, 2
Beattie, James A.; Ingersoll, Henry G.; Stockmayer, Walter H.,
Vapor Pressures and Critical Constants of Isobutene,
J. Am. Chem. Soc., 1942, 64, 3, 546-548, https://doi.org/10.1021/ja01255a021
. [all data]
Lamb and Roper, 1940
Lamb, Arthur B.; Roper, Edwin E.,
The Vapor Pressures of Certain Unsaturated Hydrocarbons,
J. Am. Chem. Soc., 1940, 62, 4, 806-814, https://doi.org/10.1021/ja01861a032
. [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]
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]
Shimanouchi, 1972
Shimanouchi, T.,
Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Vibrational and/or electronic energy levels, 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°gas Enthalpy of combustion of gas at standard conditions ΔfH°gas Enthalpy of formation of gas 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.