Kinetics of the reaction of bromine atoms with molecular fluorine

The rate constant of the reaction of bromine atoms with molecular fluorine is determined by mass spectrometrically monitoring BrF produced at fixed reaction time as a function of the concentration of F2 added to a flowing mixture of Br and Br2 in He diluent. The rate constant is 1.31×10−13 exp(−17.9 kJ mole−1/RT) cm3 molecule−1 sec−1 over the temperature range 296–418° K. Br+F2 is thus another example of the anomalously slow rate which is characteristic of the reactions of F2 with many atoms.