Mass Spectrometric Investigations of Silver Halides II: Temperature Dependence of the Mass Spectrum of Silver Chloride

Abstract

AbstractIt is shown that two effects are responsible for the temperature dependence of the mass spectrum of silver chloride: the temperature dependence of the vapor pressure in the Knudsen cell and the temperature dependence of the fragmentation reactions of the parent ions after their formation in the ionisation chamber. A procedure is demonstrated which even in this case enables us to determine enthalpies of vaporisation for monomeric and trimeric silver chloride molecules. The following results are obtainedmagnified imageFinally it was possible to derive from the experiments values for the enthalpies of vaporisation and sublimation at lower temperatures. These led to a value for the enthalpy of dissociation of AgCl (gas) into the elements: D = 305 ± kJ mol−1 (298 K), in good accordance with a value given in Part I of this series.