ISSN:
0538-8066
Keywords:
Chemistry
;
Physical Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The kinetics of the title reactions have been studied using the discharge-flow mass spectrometic method at 296 K and 1 torr of helium. The rate constant obtained for the forward reaction Br+IBr→I+Br2 (1), using three different experimental approaches (kinetics of Br consumption in excess of IBr, IBr consumption in excess of Br, and I formation), is: k1=(2.7±0.4)×10-11 cm3 molecule-1s-1. The rate constant of the reverse reaction: I+Br2→Br+IBr (-1) has been obtained from the Br2 consumption rate (with an excess of I atoms) and the IBr formation rate: k-1=(1.65±0.2)×10-13 cm3molecule-1s-1. The equilibrium constant for the reactions (1,-1), resulting from these direct determinations of k1 and k-1 and, also, from the measurements of the equilibrium concentrations of Br, IBr, I, and Br2, is: K1=k1/k-1=161.2±19.7. These data have been used to determine the enthalpy of reaction (1), ΔH298°=-(3.6±0.1) kcal mol-1 and the heat of formation of the IBr molecule, ΔHf,298°(IBr)=(9.8±0.1) kcal mol-1. © 1998 John Wiley & sons, Inc. Int J Chem Kinet 30: 933-940, 1998
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
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