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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 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 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 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.