Authors: S Vecchio
Publish Date: 2006/04/03
Volume: 84, Issue: 1, Pages: 271-278
Abstract
The standard sublimation enthalpies of 245trichlorophenoxyacetonitrile and 245trichlorophenoxyaniline were determined by isothermal thermogravimetry using the Langmuir equation and by nonisothermal differential scanning calorimetry for comparison The used procedure was previously tested using three reference compounds benzoic acid succinic acid and salicylic acid The results compared to those reported in literature show an excellent agreement for two of the three compounds while the third agrees quite well For 245trichlorophenoxyacetonitrile and 245trichlorophenoxyaniline the extrapolation of data at 29815 K were obtained respectively ΔsubH°298 K=106±4 and 101±4 kJ mol–1 From Clausius Clapeyron equation obtained after the determination of the vaporization constant α′ the following standard sublimation entropies for 245trichlorophenoxyacetonitrile and 245trichlorophenoxyaniline equal to ΔsubS°298 K=251 and 237 J K–1 mol–1 respectively were derived with an error of ±4 J K–1 mol–1 equal for the studied herbicides
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