Structural effects on the thermochemical properties of sulfur compounds: I. Enthalpy of combustion, vapour pressures, enthalpy of sublimation, and standard molar enthalpy of formation in the gaseous phase of 1,3-dithiane

Using static bomb combustion calorimetry, the combustion energy of 1-methylhydantoin was obtained, from which the standard molar enthalpy of formation of the crystalline phase at T = 298.15 K of the compound studied was calculated. Through thermogravimetry, mass loss rates were measured as a function of temperature, from which the enthalpy of vaporization was calculated. Additionally, some properties of fusion were determined by differential scanning calorimetry, such as enthalpy and temperature. Adding the enthalpy of fusion to the enthalpy of vaporization, the enthalpy of sublimation of the compound was obtained at T = 298.15 K. By combining the enthalpy of formation of the compound in crystalline phase with its enthalpy of sublimation, the respective standard molar enthalpy of formation in the gas phase was calculated. On the other hand, the results obtained in the present work were compared with those of other derivatives of hydantoin, with which the effect of the change of some substituents in the base heterocyclic ring was evaluated.

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Thermochemistry of inorganic sulfur compounds IV. Standard molar enthalpy of formation of sulfur hexafluoride

The Journal of Chemical Thermodynamics ◽

10.1016/0021-9614(85)90131-4 ◽

1985 ◽

Vol 17 (4) ◽

pp. 349-354 ◽

Cited By ~ 26

Author(s):

P.A.G O'Hare

Keyword(s):

Enthalpy Of Formation ◽

Sulfur Hexafluoride ◽

Sulfur Compounds ◽

Molar Enthalpy ◽

Standard Molar Enthalpy ◽

Inorganic Sulfur

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Thermochemistry of inorganic sulfur compounds III. The standard molar enthalpy of formation at 298.15 K of US1.992 (β-uranium disulfide) by fluorine bomb calorimetry

The Journal of Chemical Thermodynamics ◽

10.1016/0021-9614(84)90189-7 ◽

1984 ◽

Vol 16 (12) ◽

pp. 1175-1180 ◽

Cited By ~ 3

Author(s):

J.L. Settle ◽

P.A.G. O'Hare

Keyword(s):

Enthalpy Of Formation ◽

Sulfur Compounds ◽

Molar Enthalpy ◽

Standard Molar Enthalpy ◽

Bomb Calorimetry ◽

Inorganic Sulfur ◽

Fluorine Bomb Calorimetry

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Heat Capacities and Standard Molar Enthalpy of Formation of Butyl 4-Hydroxybenzoate (C11H14O3)

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.525.133 ◽

2014 ◽

Vol 525 ◽

pp. 133-140 ◽

Cited By ~ 1

Author(s):

Qing Fen Meng ◽

Dong Hai Zhu ◽

Zhi Cheng Tan ◽

Ya Ping Dong ◽

Wu Li

Keyword(s):

Enthalpy Of Formation ◽

Adiabatic Calorimeter ◽

Heat Capacities ◽

Molar Enthalpy ◽

Enthalpy Of Combustion ◽

Thermodynamic Quantities ◽

Standard Molar Enthalpy ◽

Thermochemical Cycle ◽

Volume Energy ◽

Combustion Calorimeter

Low-temperature heat capacities of butyl 4-hydroxybenzoate have been measured by a high precision automated adiabatic calorimeter over the temperature range from 79 to 399 K. The melting temperature, the molar enthalpy and entropy of the phase transition were determined to be (342.227 ± 0.054) K, (26.122 ± 0.192) kJmol-1and (76.33 ± 0.55) JK-1mol-1.The thermodynamic functions (HT-H298.15K) and (ST-S298.15K) were calculated in the range from 80 to 400 K with the interval of 5 K. The constant-volume energy and standard molar enthalpy of combustion have been determined,cU (C11H14O3,s) =-(5760.30 ± 2.70) kJmol-1andcHm0(C11H14O3, s) =-(5765.26 ± 2.70) kJmol-1, by means of a precision oxygen-bomb combustion calorimeter atT= 298.15 K. The standard molar enthalpy of formation has been derived,fHm0(C11H14O3, s) =-( 564.16 ± 4.41) kJmol-1, from the standard molar enthalpy of combustion in combination with other auxiliary thermodynamic quantities through a Hess thermochemical cycle.

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