Rotating bomb calorimetry

W. D. Good, D. M. Fairbrother, G. Waddington. Manganese Carbonyl Heat of Formation by Rotating-Bomb Calorimetry. J. Phys. Chem. 1958, 62, 853-856. 

M. E. Minas da Piedade, L. Shaofeng, G. Pilcher. Enthalpy of Formation of Dycyclopentadienyltungsten Dichloride by Rotating-Bomb Calorimetry. 1 Chem. Thermodynamics 1987,19, 195-199. 

Finally, significant advances in the techniques of both thermal and thermochemical measurements have come to fruition in the last decade, notably aneroid rotating-bomb calorimetry and automatic adiabatic shield control, so that enhanced calorimetric precision is possible, and the tedium is greatly reduced by high speed digital computation. Non-calorimetric experimental approaches as well as theoretical ones, e.g., calculation of electronic heat capacity contributions to di- and trivalent lanthanides by Dennison and Gschneidner (33), are also adding to definitive thermodynamic functions. 

How can we assess the thermochemical data presented in Table 1 Many were obtained by static-bomb calorimetry. Regrettably, this technique is clearly unsuitable to deal with these substances due to the ill-defined composition of the combustion products (see the discussion in References 13 and 28). The formation of nonstoichiometric oxides upon combustion all but precludes the experimental rigor demanded of the combustion calorimetrist. This fact, by itself, allows us to question the reliability of the values shown for all of the trialkyl compounds and for triphenylantimony. Although the results for triphenylbismuth found by static and rotating-bomb calorimetry overlap within their error bars, this has been suggested to be fortuitous ... 

The so-derived enthalpy of formation of gaseous triphenylarsine oxide, 261 18 kcalmol , just overlaps the value obtained from rotating bomb calorimetry, 227.6 +15.6 kJ mol . While related success arises in the comparison of the values for triphenylphosphine oxide we admit our discomfort with the large error bars accompanying all of these values. As such, while we derive an enthalpy of formation of triphenylstibine oxide using the static bomb results for stibine—and thus enter this value into Table 1—we regrettably consider it pointless even to compare the E—O bond enthalpies for the three triphenyl compounds. 

In recent years, with the development of rotating-bomb calorimetry and the refinement of thermodynamic corrections for the combustion process for nitrogen and sulphur containing organic compounds, a number of accurate heats of combustion of heterocyclic compounds have been determined. 

Heats of formation have since been reported for some 150 or more organometallic compounds, but several of these are of doubtful reliability. However, the development of rotating-bomb calorimetry and the application of novel reaction calorimetric techniques have provided more effective means than hitherto for investigating the thermochemistry of organometallic compounds, making it almost certain that the present lack of reliable data will be short-lived. 

Mortimer and Sellers 123) measured the heat of combustion using rotating-bomb calorimetry Ph3As was burned in O2, in the presence of aqueous sodium hydroxide. The product was a homogeneous solution containing sodium arsenite, sodium arsenate, sodium carbonate, and sodium hydroxide. After analyzing the solution, corrections were made to allow for the heat effects due to formation of sodium carbonate and sodium arsenate. For the ideal reaction,... 

Combustion or bomb calorimetry is used primary to derive enthalpy of fonuation values and measurements are usually made at 298.15 K. Bomb calorimeters can be subdivided into tluee types (1) static, where the bomb or entire calorimeter (together with the bomb) remains motionless during the experiment (2) rotating-... 

IMR = ion-molecule reactions RB = rotating-bomb combustion calorimetry RC = reaction calorimetry SB = static-bomb combustion calorimetry. 

There is general agreement that static-bomb combustion calorimetry is inherently unsatisfactory to determine enthalpies of formation of organolead compounds2,3. Unfortunately, as shown in Table 6 only three substances have been studied by the rotating-bomb method. The experimentally measured enthalpies of formation of the remaining compounds in Table 6 were determined by reaction-solution calorimetry and all rely on AH/(PbPh4, c). 

R. C. Santos, H. P. Diogo, M. E. Minas daPiedade. The Determination of the Standard Molar Enthalpy of Formation of 4-Chlorobenzoic Acid by Micro Rotating-Bomb Combustion Calorimetry.J. Chem. Thermodynamics 1999, 31, 1417-1427. 

C. A.Neugebauer, "Standard Heats of Formation by Rotating and Stationary Bomb Calorimetry ,... 

Chemists always need to know bond energies, often for unusual combinations of elements, for which bomb combustion calorimetry experiments have never been done, partly because the appetite of conventional bomb combustion calorimeters for large samples is not easily met for rare compounds. Thus there is a need for future micro rotating-bomb calorimeters. 

Numerous oxidation tests are available to screen vegetable oil oxidative stability including thin film oxygen uptake test (TFOUT, ASTM D 4/42), rotating bomb oxidation test (RBOT, ASTM D 2272), panel coker test, and pressurized differential scanning calorimetry (Biswas et al., 2007 Erhan et al., 2006 Sharma et al., 2005,... 

W. N. Hubbard, C. Katz, and G. Waddington, A rotating combustion bomb for precision calorimetry. Heats of combustion of some sulfur-containing compounds,. Phys. Chem. 58 142-152 (1954). 

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