A Mass Spectrometric Study of Vaporization of Li2O with Some Refractory Metal Cells

The vapor pressure of lithium monoxide(Li2O)has been obtained by high temperature mass spectrometry. The partial pressures of Li, O2 and Li2O gaseous molecules have been determined experimentally and several thermodynamic data for the reaction (1)Li2O(s)=2Li(g)+1/2O2 and for the reaction(2)Li2O(s)=Li2O(g)have been calculated. The third law enthalpy ΔH0o;obtained for the reaction(1)is 909 ±4 kjoule mole-1;, being in good agreement with published data. The minor vapor species such as LiO, Li3O and Li2O2 were also detected. A compatibility investigation has been undertaken using Knudsen effusion cells fabricated from various refractory metals. The order of oxidation of refractory with Li2O has been determined as follows, Pt