Bomb calorimeter calorimetry, precision

Methods of Organic Chemistry , Interscience, NY, vol l,part 1(1959), 523-654 J.M.Sturtevant, "Calorimetry 26)R.S.Jessup, "Precise Measurements of Heats of Combustion with a Bomb Calorimeter , USNBS Monograph No 7, Washington, DC(1960) 27)S.Glasstone D.Lewis "Elements of Physical Chemistry , VanNostrand, NY(1960) 28)Merriam-Websters (1961), 320 29)Parr Specifications No 1100- 1105 (Describes various bombs and calorimeter and gives literature on Parr apparatuses may be obtained on request from Parr Instrument Co, Moline, Illinois)... 

Constant-Volume Calorimetry In the coffee-cup calorimeter, we assume all the heat is gained by the water, but some must be gained by the stirrer, thermometer, and so forth. For more precise work, as in constant-volume calorimetry, the heat capacity of the entire calorimeter must be known. One type of constant-volume apparatus is the bomb calorimeter, designed to measure very precisely the heat released in a combustion reaction. As Sample Problem 6.5 will show, this need for greater precision requires that we know (or determine) the heat capacity of the calorimeter. 

Much of the accuracy in bomb calorimetry depends upon the care taken in the construction of the auxiliary equipment of the calorimeter, also called the addenda. It must be designed such that the heat flux into or out of the measuring water is at a minimum, and the remaining flux must be amenable to a calibration. In particular, the loss due to evaporation of water must be kept to a minimum, and the energy input from the stirrer must be constant throughout the experiment. With an apparatus such as shown in Fig. 4.30 anyone can reach, with some care, a precision of 1%, but it is possible by most careful bomb calorimetry to reach an accuracy of 0.01%. 

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