Mass Spectrometric Study of the Evaporation of Lithium and Sodium Molybdates and Tungstates

摘要

The vapor phases in equilibrium with lithium molybdate, lithium tungstate, sodium molybdate and sodium tungstate salts were investigated by a mass spectrometric Knudsen effusion technique in the temperature range 1200 to 1800K. Lithium molybdate and tungstate evaporate mainly as molecular Li2MoO4(g) and Li2WO4(g). Sodium molybdate and tungstate are reduced by the cricible material to yield Na(g) and MoO2(g) and WO2(g), respectively. Heats of dissociation of Li2MoO4(g) and Li2WO4(g) to Li2O(g) and MoO3(g) and to Li2O(g) and WO3(g) are given.