VAPOR COMPOSITION AND PRESSURE OVER CHLORIDES OF SILVER AND GOLD

Using high-temperature mass spectrometry, the thermodynamics of vapori zation of silver chloride and gold trichloride: were studied in the 79 0 - 920 and 370 - 400 K temperature ranges. respectively. Silver chlor ide vaporizes congruently to form. in the vapor phase, monomeric. trim eric and, to a lesser extent, tetrameric molecules. The partial pressu res of the monomer and trimer molecules over silver chloride were meas ured. Gold trichloride vaporizes congruently up to 400 K forming dimer ic molecules. At higher temperatures. it dissociates to the monochlori de following a condensate mechanism. The vapor pressure and the heat o f vaporization of gold trichloride were determined.