Difluoromethane

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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
Δfgas-450.66kJ/molReviewChase, 1998Data last reviewed in December, 1969
Δfgas-452.21 ± 0.92kJ/molCcrNeugebauer and Margrave, 1958Corrected for CODATA value of ΔfH; ALS
Quantity Value Units Method Reference Comment
Δcgas-583.08kJ/molCcrNeugebauer and Margrave, 1958Corrected for CODATA value of ΔfH; ALS
Quantity Value Units Method Reference Comment
gas,1 bar246.70J/mol*KReviewChase, 1998Data last reviewed in December, 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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. to 1200.1200. to 6000.
A -6.09868294.67555
B 179.22006.983473
C -122.3682-1.341897
D 32.302070.089387
E 0.491361-18.07061
F -454.1439-519.5482
G 193.7979307.0742
H -450.6586-450.6586
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1969 Data last reviewed in December, 1969

References

Go To: Top, Gas phase thermochemistry data, 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]

Neugebauer and Margrave, 1958
Neugebauer, C.A.; Margrave, J.L., The heats of formation of CHF3 and CH2F2, J. Phys. Chem., 1958, 62, 1043-1048. [all data]


Notes

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