Ethane, hexafluoro-
- Formula: C2F6
- Molecular weight: 138.0118
- IUPAC Standard InChIKey: WMIYKQLTONQJES-UHFFFAOYSA-N
- CAS Registry Number: 76-16-4
- 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: Perfluoroethane; F-116; Freon 116; Hexafluoroethane; C2F6; Fluorocarbon 116; UN 2193; Freon 1166SY; 1,1,1,2,2,2-Hexafluoroethane; R 116; Ethane, 1,1,1,2,2,2-hexafluoro-; HFC 116
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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
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | -321.200 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1969 |
ΔfH°gas | -321.2 ± 1.2 | kcal/mol | Eqk | Walker, Sinke, et al., 1970 | ALS |
ΔfH°gas | -318. | kcal/mol | Eqk | Coomber and Whittle, 1967 | ALS |
ΔfH°gas | -318. ± 2. | kcal/mol | Ccb | Sinke, 1966 | ALS |
ΔfH°gas | -321.22 ± 0.96 | kcal/mol | Cm | Kirkbride and Davidson, 1954 | Reanalyzed by Kolesov and Papina, 1983, Original value = -303. ± 2. kcal/mol; Von Wartenberg method; ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 79.371 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1969 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
E/t2
H° − H°298.15= A*t + B*t2/2 +
C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 −
E/(2*t2) + G
Cp = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 1400. | 1400. to 6000. |
---|---|---|
A | 16.67000 | 42.29259 |
B | 53.86231 | 0.244591 |
C | -41.62591 | -0.046148 |
D | 11.26830 | 0.002604 |
E | -0.347915 | -2.671979 |
F | -329.3929 | -341.5901 |
G | 83.28021 | 118.6850 |
H | -321.2000 | -321.2000 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in June, 1969 | Data last reviewed in June, 1969 |
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 by: Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
S°liquid | 59.880 | cal/mol*K | N/A | Pace and Aston, 1948 |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
31.38 | 195. | Pace and Aston, 1948 | T = 12 to 195 K. |
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
DH - Eugene S. Domalski and Elizabeth D. Hearing
AC - William E. Acree, Jr., James S. Chickos
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 |
---|---|---|---|---|---|
Tboil | 195. ± 2. | K | AVG | N/A | Average of 12 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 173.1 | K | N/A | Thorp and Scott, 1956 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 172.65 | K | N/A | Ruff and Bretschneider, 1933 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 166.85 | K | N/A | Swarts, 1933 | Uncertainty assigned by TRC = 0.02 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 173.08 | K | N/A | Lobo and Staveley, 1979 | Uncertainty assigned by TRC = 0.005 K; TRC |
Ttriple | 173.10 | K | N/A | Pace and Aston, 1948, 2 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.02 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ptriple | 0.2591 | atm | N/A | Lobo and Staveley, 1979 | Uncertainty assigned by TRC = 0.00004 atm; TRC |
Ptriple | 0.2986 | atm | N/A | Swarts, 1933 | Uncertainty assigned by TRC = 0.0001 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 292.8 | K | N/A | Majer and Svoboda, 1985 | |
Tc | 293.030 | K | N/A | Saikawa, Kijima, et al., 1979 | Uncertainty assigned by TRC = 0.01 K; TRC |
Tc | 293.01 | K | N/A | Kijima, Saikawa, et al., 1977 | Uncertainty assigned by TRC = 0.01 K; TRC |
Tc | 292.66 | K | N/A | Kim, 1974 | Uncertainty assigned by TRC = 0.05 K; TRC |
Tc | 292.85 | K | N/A | Swarts, 1933 | Uncertainty assigned by TRC = 0.05 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 30.02 | atm | N/A | Saikawa, Kijima, et al., 1979 | Uncertainty assigned by TRC = 0.08 atm; derived from published vapor pressure data; TRC |
Pc | 30.00 | atm | N/A | Kijima, Saikawa, et al., 1977 | Uncertainty assigned by TRC = 0.011 atm; TRC |
Pc | 29.7361 | atm | N/A | Kim, 1974 | Uncertainty assigned by TRC = 0.0340 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ρc | 4.51 | mol/l | N/A | Saikawa, Kijima, et al., 1979 | Uncertainty assigned by TRC = 0.072 mol/l; TRC |
ρc | 4.20 | mol/l | N/A | Kijima, Saikawa, et al., 1977 | Uncertainty assigned by TRC = 0.14 mol/l; TRC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
3.8599 | 194.87 | N/A | Pace and Aston, 1948 | P = 101.325 kPA; DH |
4.13 | 186. | A | Stephenson and Malanowski, 1987 | Based on data from 172. to 200. K.; AC |
3.860 | 195. | N/A | Majer and Svoboda, 1985 | |
4.09 | 188. | N/A | Pace and Aston, 1948 | Based on data from 180. to 196. 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 |
---|---|---|---|---|---|
180. to 195. | 5.810 | 0.232 | 292.8 | Majer and Svoboda, 1985 |
Entropy of vaporization
ΔvapS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
19.81 | 194.87 | Pace and Aston, 1948 | P; DH |
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 |
---|---|---|---|---|---|
179.96 to 195.21 | 3.97442 | 677.112 | -24.506 | Pace and Aston, 1948 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
6.21 | 103. | Bondi, 1963 | See also Pace and Aston, 1948.; AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
0.643 | 173.1 | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
8.58 | 104.0 | Domalski and Hearing, 1996 | CAL |
3.70 | 173.1 |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.8929 | 103.98 | crystaline, II | crystaline, I | Pace and Aston, 1948 | DH |
0.6420 | 173.10 | crystaline, I | liquid | Pace and Aston, 1948 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
8.587 | 103.98 | crystaline, II | crystaline, I | Pace and Aston, 1948 | DH |
3.709 | 173.10 | crystaline, I | liquid | Pace and Aston, 1948 | DH |
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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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
By formula: 3C2F6 + 2F3N = 6CF4 + N2
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -311.7 ± 3.0 | kcal/mol | Ccb | Sinke, 1966 | gas phase |
By formula: C2N2 + C2F6 = 2C2F3N
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 10.54 ± 0.14 | kcal/mol | Eqk | Walker, Sinke, et al., 1970 | gas phase |
By formula: C2F6 + Br2 = 2CBrF3
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 3.66 ± 0.14 | kcal/mol | Eqk | Coomber and Whittle, 1967 | gas phase |
Henry's Law 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 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 |
---|---|---|---|---|
0.000058 | Q | N/A | missing citation give several references for the Henry's law constants but don't assign them to specific species. |
IR Spectrum
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Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Data compiled by: Pamela M. Chu, Franklin R. Guenther, George C. Rhoderick, and Walter J. Lafferty
- gas; IFS66V (Bruker); 3-Term B-H Apodization
0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm-1 resolution - gas; IFS66V (Bruker); Boxcar Apodization
0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm-1 resolution - gas; IFS66V (Bruker); Happ Genzel Apodization
0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm-1 resolution - gas; IFS66V (Bruker); NB Strong Apodization
0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm-1 resolution - gas; IFS66V (Bruker); Triangular Apodization
0.1250, 0.2410, 0.4820, 0.9640, 1.9290 cm-1 resolution
Mass spectrum (electron ionization)
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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
Spectrum
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Additional Data
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Due to licensing restrictions, this spectrum cannot be downloaded.
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 | 3610 |
Vibrational and/or electronic energy levels
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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: Takehiko Shimanouchi
Symmetry: D3d Symmetry Number σ = 6
Sym. | No | Approximate | Selected Freq. | Infrared | Raman | Comments | ||||
---|---|---|---|---|---|---|---|---|---|---|
Species | type of mode | Value | Rating | Value | Phase | Value | Phase | |||
a1g | 1 | CC str | 1228 | D | ia | 1228 | gas | OC ( )Mean value of frequencies obtained from six combination bands. | ||
a1g | 2 | CF3 s-str | 807 | C | ia | 807 VS p | gas | |||
a1g | 3 | CF3 s-deform | 348 | C | ia | 348 W p | gas | |||
a1u | 4 | Torsion | 68 | D | ia | ia | CF | |||
a2u | 5 | CF3 s-str | 1117 | B | 1117 VS | gas | ia | |||
a2u | 6 | CF3 s-deform | 714 | B | 714 VS | gas | ia | |||
eg | 7 | CF3 d-str | 1250 | C | ia | 1250 VW dp | gas | |||
eg | 8 | CF3 d-deform | 619 | C | ia | 619 W dp | gas | |||
eg | 9 | CF3 rock | 372 | C | ia | 372 W dp | gas | |||
eu | 10 | CF3 d-str | 1251 | B | 1251 VS | gas | ia | |||
eu | 11 | CF3 d-deform | 520 | C | 520 S | gas | ia | |||
eu | 12 | CF3 rock | 220 | C | 220 S | gas | ia | |||
Source: Shimanouchi, 1972
Notes
VS | Very strong |
S | Strong |
W | Weak |
VW | Very weak |
ia | Inactive |
p | Polarized |
dp | Depolarized |
OC | Frequency estimated from an overtone or a combination tone indicated in the parentheses. |
CF | Calculated frequency |
B | 1~3 cm-1 uncertainty |
C | 3~6 cm-1 uncertainty |
D | 6~15 cm-1 uncertainty |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), 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.
Chase, 1998
Chase, M.W., Jr.,
NIST-JANAF Themochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
Walker, Sinke, et al., 1970
Walker, L.C.; Sinke, G.C.; Perettie, D.J.; Janz, G.J.,
Enthalpy of formation of trifluoroacetonitrile,
J. Am. Chem. Soc., 1970, 92, 4525-4526. [all data]
Coomber and Whittle, 1967
Coomber, J.W.; Whittle, E.,
Bond dissociation energies from equilibrium studies. Part 2.-D(CF3-CF3) and enthalpy of formation of C2F6,
Trans. Faraday Soc., 1967, 63, 1394-1401. [all data]
Sinke, 1966
Sinke, G.C.,
The heat of reaction of nitrogen trifluoride and hexafluoroethane,
J. Phys. Chem., 1966, 70, 1326-1327. [all data]
Kirkbride and Davidson, 1954
Kirkbride, F.W.; Davidson, F.G.,
Heats of formation of gaseous fluoro- and fluorochloro-carbons,
Nature (London), 1954, 174, 79-80. [all data]
Kolesov and Papina, 1983
Kolesov, V.P.; Papina, T.S.,
Thermochemistry of Haloethanes,
Russ. Chem. Rev., 1983, 52, 425. [all data]
Pace and Aston, 1948
Pace, E.L.; Aston, J.G.,
The thermodynamics of hexafluoroethane from calorimetric and spectroscopic data,
J. Am. Chem. Soc., 1948, 70, 566-570. [all data]
Thorp and Scott, 1956
Thorp, N.; Scott, R.L.,
Fluorocarbon solutions at low termperatures. I. The liquid mixtures CF4-CHF3, CF4-CH4, CF4-Kr, CH4-Kr.,
J. Phys. Chem., 1956, 60, 670. [all data]
Ruff and Bretschneider, 1933
Ruff, O.; Bretschneider, O.,
The Preparation of Hexafluoroethane and Tetrafluoroethene from Tetrafluoromethane,
Z. Anorg. Allg. Chem., 1933, 210, 173. [all data]
Swarts, 1933
Swarts, F.,
Hexafluoroethane.,
Bull. Soc. Chim. Belg., 1933, 42, 114. [all data]
Lobo and Staveley, 1979
Lobo, L.Q.; Staveley, L.A.K.,
The vapour pressure of tetrafluoromethane.,
Cryogenics, 1979, 19, 335. [all data]
Pace and Aston, 1948, 2
Pace, E.L.; Aston, J.G.,
The thermodynamics of hexafluoroethane from calorimetric and spectroscopic data,
J. Am. Chem. Soc., 1948, 70, 566. [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]
Saikawa, Kijima, et al., 1979
Saikawa, K.; Kijima, J.; Uematsu, M.; Watanabe, K.,
Determination of the critical temperature and density of hexafluoroethane,
J. Chem. Eng. Data, 1979, 24, 165-7. [all data]
Kijima, Saikawa, et al., 1977
Kijima, J.; Saikawa, K.; Watanabe, K.; Oguchi, K.; Tanishita, I.,
Experimental study of thermodyn. prop. of hexafluoroethane (R116)
in Proc. Symp. Thermophys. Prop., 7th, Cezairliyan, A., Ed., ASME: New York, p 480, 1977. [all data]
Kim, 1974
Kim, K.Y.,
Calorimetric studies on argon and Hexafluoroethane and a generalized correlation of maxima in isobaric heat capacity., Ph.D. Dissertation, Univ. Mich., Ann Arbour, MI, 1974. [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]
Bondi, 1963
Bondi, A.,
Heat of Siblimation of Molecular Crystals: A Catalog of Molecular Structure Increments.,
J. Chem. Eng. Data, 1963, 8, 3, 371-381, https://doi.org/10.1021/je60018a027
. [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, Reaction thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid Pc Critical pressure Ptriple Triple point pressure S°gas,1 bar Entropy of gas at standard conditions (1 bar) S°liquid Entropy of liquid at standard conditions Tboil Boiling point Tc Critical temperature Tfus Fusion (melting) point Ttriple Triple point temperature 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 ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrH° Enthalpy of reaction at standard conditions ΔsubH Enthalpy of sublimation ΔvapH Enthalpy of vaporization ΔvapS Entropy of vaporization ρc Critical density - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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