Fluorine combustion "bomb calorimeter

Apparatus and Procedure. The thermochemical measurements were made using a Parr fluorine combustion bomb and a National Bureau of Standards (NBS) isothermal calorimeter (No. 63090) manufactured bv the Precision Scientific Co. The bomb cylinder and all internal parts or the bomb were Monel. A Monel ampoule was fitted into the top of the bomb to retain the OF2 sample. The ampoule apparatus reduced the internal volume of the bomb from 380 to 315 cc. The ampoule screws... 

The standard calorimeter system for this series of experiments was specified as the NBS calorimeter containing the Parr fluorine combustion bomb plus sample ampoule. The standard bomb was defined as the Parr fluorine combustion bomb plus sample ampoule minus the water, the benzoic acid pellet, the Hastelloy cup containing the pellet, the oxygen, and the nitrogen used to pressurize the ampoule. 

Only six other centers have operated similar metal bomb calorimeters, mainly modeled on the Hubbard design, and it is therefore of interest to note that Gross and co-workers have been intrepid enough to use a simple two-compartment glass apparatus separated by a break-seal for fluorine combustion (5 atm F2). Their results were in excellent agreement with those obtained in metal bombs (107). 

The obtained A 7 a() value and the energy equivalent of the calorimeter, e, are then used to calculate the energy change associated with the isothermal bomb process, AE/mp. Conversion of AE/ibp to the standard state, and subtraction from A f/jgp of the thermal corrections due to secondary reactions, finally yield Ac f/°(298.15 K). The energy equivalent of the calorimeter, e, is obtained by electrical calibration or, most commonly, by combustion of benzoic acid in oxygen [110,111,113]. The reduction of fluorine bomb calorimetric data to the standard state was discussed by Hubbard and co-workers [110,111]. 

Recently, Rudzitis et al. (6) measured the enthalpy of combustion of PF in fluorine in a two-chambered bomb calorimeter at... 

A beam type of vacuum microbalance constructed from aluminium, nickel, and fluorite parts has been described 13 it was used to study corrosion of Si by F2 and Si02 by HF. A simple, new two-chamber fluorine bomb calorimeter has the advantage that a high F2 concentration can be used during the combustion.14 The same group of Russian workers have measured the enthalpy of combustion of Cu and W in this way.15 Ader has determined the energy of the reaction ... 

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