The determination of the standard molar enthalpy of formation of 4-chlorobenzoic acid by micro rotating-bomb combustion calorimetry

Critical Evaluation of Thermodynamic Properties for Halobenzoic Acids Through Consistency Analyses for Results from Experiment and Computational Chemistry

“…The large number of combustion studies for 4-chlorobenzoic acid reflects its development and long acceptance as a reference material for the combustion of organic chlorine compounds. [97][98][99][101][102][103][104][105][106][107][108][109][110][111][112][113][114] The agreement amongst nearly twenty measurement results is excellent, as seen in Table 7. Table 8.…”

Enthalpy of formation of benzo[k]fluoranthene

“…(30) Correction of this result to T = 298.15 K by using equations (5) and (6), and the (31) Gavezzotti and Desiraju (128.2 kJ · mol −1 ), (32) and Nass et al (130.3 kJ · mol −1 ). (33) The results of the combustion calorimetric experiments are shown in table 2, where m(C 20 H 12 ) is the mass of benzo[k]fluoranthene; m(aux) is the mass of n-hexadecane used as the combustion auxiliary; n(HNO 3 ) is the amount of substance of nitric acid formed in the bomb process; ε i and ε f are the energy equivalents of the bomb contents in the initial and final states of the bomb process, respectively; T i and T f represent the initial and final temperatures of the experiment; T c is the contribution to the observed temperature rise of the calorimeter proper due to the heat exchanged with the surroundings and the heat dissipated by the temperature sensor; U ign is the electrical energy supplied for ignition of the sample; U IBP is the internal energy change associated with the bomb process under isothermal conditions, at T = 298.15 K; U represents the sum of all corrections necessary to reduce U IBP to the standard state; U (HNO 3 ) is the energy change associated with the formation of nitric acid; U (aux) and U (C 20 The values of T i , T f , and T c were calculated by using a computer programme based on the Regnault-Pfaundler method, (19) and U IBP was obtained from: (34) …”

“…The analysis of the HNO 3 (aq) formed from traces of atmospheric N 2 initially present inside the bomb, was performed using a Dionex 4000i ion chromatography apparatus. (20) In a typical calorimetric experiment, a pellet of benzo[k]fluoranthene with a diameter of ca. 4 mm was placed in a platinum crucible containing n-hexadecane and weighed to ±10 −7 g in a Sartorius 4504 Mp8-1 ultra-micro balance.…”

“…The combustion calorimetric experiments were performed using a micro-combustion calorimeter previously described. (19,20) The energy equivalent of the calorimeter and its standard deviation ε o = (1809.65 ± 0.27) J · K −1 was previously determined from the combustion of benzoic acid (B.D.H. thermochemical standard) whose standard massic energy of combustion under the certificate conditions was −(26433 ± 4) J · g −1 .…”

Thermochemistry of 2- and 4-biphenylmethanol

“…Details of the apparatus and the general experimental procedure have been described [10,11]. In a typical experiment, a pellet of the compound under study (ca.…”