Viscosities and Surface Tension of some Liquid Halogen Fluorides

Abstract

Values of the surface tension and viscosity of iodine pentafluoride, bromine pentafluoride and bromine trifluoride have been measured in the liquid phase over a range of temperature with a precision of plus or minus 2% and the data have been fitted to empirical equations. By application of the Eyring theory of viscosity the heats and free energies of activation for viscous flow have been computed and are compared with the energies of vaporization. These results, along with the Trouton constants and the dielectric constants, indicate that iodine pentafluoride and bromine trifluoride are associated in the liquid phase, whereas chlorine trifluoride and bromine pentafluoride probably are normal.