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In an isoperibolic calorimeter with a stationary bomb, the value of the combustion energy of crystalline β-alanine (ΔcU0) was determined at 298.15 K, from which standard enthalpies of combustion (ΔcU0) and formation (ΔcU0) have been calculated. The obtained results are compared with literature data.

The enthalpy of the combustion of C60Br24 · 2Br2 has been measured using a rotating-bomb calorimeter as follows: Δ c H 0(C60Br24 · 2Br2, cr) = (−25986 ± 166) kJ/mol. The result has been used to calculate the standard enthalpy of formation, ΔfH 0(C60Br24 · 2Br2, cr) = (2375 ± 166) kJ/mol. The enthalpies of formation of C60Br24 (cr) and dissociation of the C-Br bond have been estimated. The latter value has been compared with enthalpies for the C-X (X = H, F, Cl, Br) bonds in fullerene derivatives and organic compounds.

The energies of combustion, Δ c U 0, of three amino acids: L-serine (I), L-arginine (II) and L-tyrosine (III) in the crystalline state at 298.15 K were determined using a static-bomb isoperibolic calorimeter. From these data, the enthalpies of combustion, Δ c H 0, and the enthalpies of formation, Δ f H 0, are calculated. The Δ f H 0 values are compared with the published data.

The standard enthalpy of combustion of crystalline silver pivalate, (CH3)3CC(O)OAg (AgPiv), was determined in an isoperibolic calorimeter with a self-sealing steel bomb, ΔcH0 (AgPiv, cr)= −2786.9±5.6 kJ mol−1. The value of standard enthalpy of formation was derived for crystalline state: ΔfH0(AgPiv,cr)= −466.9±5.6 kJ mol−1. Using the enthalpy of sublimation, measured earlier, the enthalpy of formation of gaseous dimer was obtained: ΔfH0(Ag2Piv2,g)= −787±14 kJ mol−1. The enthalpy of reaction (CH3)3CC(O)OAg(cr)=Ag(cr)+(CH3)3CC(O)O.(g) was estimated, ΔrH0=202 kJ mol−1.

The enthalpy of combustion of crystalline fullerene fluoride C60F18 was determined in an isoperibolic calorimeter with a rotating platinized bomb, and the enthalpy of formation of the compound was calculated. The enthalpy of sublimation of C60F18 measured earlier was used to calculate the enthalpy of formation of fullerene fluoride in the gas phase and the mean enthalpy of dissociation of C-F bonds in this compound.

A rotating-bomb calorimeter was used to measure the energy of combustion of crystalline fullerene chloride C60Cl30 · 0.09Cl2, Δc U° = (−24474 ± 135 kJ/mol). The result was used to calculate the standard enthalpy of formation, Δf H° (C60Cl30, cr) = 135 ± 135 kJ/mol, and the C-Cl bond energy, 195 ± 5 kJ/mol. The C-X (X = F, F, Cl, and Br) bond energies in fullerene C60 derivatives and other organic compounds are compared.

The energy of combustion of crystalline 1,2,3,4-tetrachlorodibenzo-p-dioxine (-5122.9 ± 7.4 kJ/mol) was measured using an isothermic-shell calorimeter with a rotating platinum plated bomb. The result was used to calculate the enthalpy of combustion (-5120.4 ± 7.4 kJ/mol) and formation (−267.8 ± 7.6 kJ/mol) for the crystalline state. The enthalpy of sublimation was measured using a Calvet microcalorimeter at 411.5 K (116.0 ± 2.6 kJ/mol); recalculation to T = 298.15 K gave 118.7 ± 2.6 kJ/mol. The enthalpy of formation of 1,2,3,4-tetrachlorodibenzo-p-dioxine in the gas state was calculated (−149.1 ± 8.0 kJ/mol)

The standard molar enthalpy of combustion of 2-chlorodibenzo- p -dioxin was redetermined using the sample of high purity by rotating-bomb calorimetry: Δ c H 0 m (cr)=−(5558.2±3.5) kJ · mol −1 . The values of standard molar enthalpies of formation were derived for crystalline and gaseous states: Δ f H 0 m (cr)=−(187.9±3.8) kJ · mol −1 and Δ f H 0 m (g)=−(90.7±3.8) kJ · mol −1 .

The energy of combustion Δ c U 0 of fluorinated graphite CF0.96 has been determined using an isoperibolic calorimeter with a rotating platinized bomb and the enthalpy of formation Δ f H 0 thereof has been calculated. The enthalpy of the dissociation of the C-F bond has been calculated from the obtained value of Δ f H0(CF0.96) and compared with analogous values for the previously investigated C60 fullerene fluorides.

The standard molar enthalpy of combustion of fluorinated fullereneC60F48 was determined by rotating-bomb calorimetry,ΔcHmo = − (24638 ± 163)kJ · mol − 1. Using this result and the standard molar enthalpy of sublimation,ΔsubHmo = (109 ± 7)kJ · mol − 1, the values of the standard molar enthalpies of formation of C60F48in the crystalline and gaseous states were found to be − (7563 ± 166)kJ · mol − 1and − (7454 ± 166)kJ · mol − 1, respectively. The enthalpy of reaction C60F48(g) = C60(g) + 48F(g) was calculated,ΔrHmo (298.15 K) = (13800 ± 167)kJ · mol − 1, orΔrHmo (298.15K ) / 48 = (287.5 ± 3.5)kJ · mol − 1.

The standard molar enthalpy of combustion of crystalline 2,3-dichlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry: ΔcHm°=−(5406.4±6.6) kJ·mol−1. Using this result and the standard molar enthalpy of sublimation, ΔsubHm°=(108.6±1.0) kJ·mol−1, the values of the standard molar enthalpies of formation of 2,3-dichlorodibenzo-p-dioxin in the crystalline and gaseous states were found to be −(220.5±6.8) kJ·mol−1and −(111.9±6.9) kJ·mol−1, respectively. The standard molar enthalpy of formation of gaseous 2,3,7,8-tetrachlorodibenzo-p-dioxin was estimated: ΔfHm°(g)≈−164.6 kJ·mol−1.

The standard molar energy of combustion of crystalline 2-chlorodibenzo-p-dioxin was determined by rotating-bomb calorimetry: ΔcUm°= −(5573.6±2.8)kJ·mol−1. The standard molar enthalpy of sublimation was measured in a Calvet microcalorimeter: ΔsubHm°= (97.24±0.55) kJ·mol−1. Using these results, the values of the standard molar enthalpies of formation of 2-chlorodibenxo-p±dioxin in the crystalline and gaseous states were found to be −(171.3 ±3.2)kJ·mol−1and −(74.1±3.3)kJ·mol−1and −(74.1-3.3)kJ·mol−1, respectively.

The standard molar enthalpy of combustion of fluorofullerene C60F36 was determined by rotating-bomb calorimetry, ΔcH°m = −24692 ± 199 kJ·mol-1. Using this result and the standard molar enthalpy of sublimation, ΔsubH°m = 139 ± 8 kJ·mol-1, the values of the standard molar enthalpies of formation of C60F36 in the crystalline and gaseous states were found to be −5362 ± 201 kJ·mol-1and −5223 ± 201 kJ·mol-1, respectively. The enthalpy of reaction C60F36(g) = C60(g) + 36F(g) was calculated, ΔrH°m(298.15 K) = (10617 ± 202) kJ·mol-1, or 294.9 ± 5.6 kJ·mol-1 per one C−F bond. The comparison with the enthalpy of reaction C60F48 = C60(g) + 48F(g), ΔrH°m(298.15 K) = 287.5 ± 3.5 kJ·mol-1 per C−F bond leads to a preliminary conclusion that C−F bond enthalpy decreases with amount of F atoms attached to the fullerene cage.

The energies of combustion of perfluoro(2-methyl-3-oxa)hexanoic and perfluoro(2,5-dimethyl-3,6-dioxa)nonanoic acids are for the first time measured in a calorimeter with a rotating platinized bomb and used to calculate the standard enthalpies of formation of these compounds in the liquid state. Based on the enthalpies of formation, the contribution from the [-CF2OCF(CF3)-] group to the enthalpies of formation of perfluoro acids is calculated.

The enthalpies of formation of dibenzo-p-dioxin and its polychlorinated derivatives have been measured, and a complete set of the enthalpies of formation has been constructed.

The energy of combustion of perfluoro-2,7-dimethyloctane has been measured in a rotating bomb calorimeter, Δ c U 0 (1) = −3198.2 ± 8.6 kJ mol −1 . The enthalpy of formation, Δ f H 0 (1) has been obtained by combination of the experimental data with the accepted values for the enthalpies of formation of water, carbon dioxide and aqueous hydrofluoric acid.

Data on the thermochemistry of haloethanes are surveyed. The most reliable standard enthalpies of formation of 37 haloethanes are recommended on the basis of a critical analysis of the experimental results published up to 1980 inclusive (and partly in 1981). The constants of a computational scheme for the estimation of the enthalpies of formation of hitherto uninvestigated haloethanes have been evaluated by the method of least squares. The enthalpies of formation of 210 haloethanes containing H, F, Cl, and Br have been calculated with the aid of these constants. The bibliography includes 131 references.

The energies of combustion of two isomers of trifluorochlorobromoethane have been determined by rotating-bomb calorimetry. The values of the enthalpies of formation: ΔHfo(CF3CHClBr, g) = −(690.4 ± 4.9) kJ mol−1 and ΔHfo(CF2BrCHFCl, g) = −(644.8 ± 6.4) kJ mol−1 were derived. Using the latter value, the enthalpy of formation of trifluorochloroethylene CF2:CFCl was found to be −(500.0 ± 6.5) kJ mol−1.