Mass Spectrometric Study of Alkali Hydroxide Vapors

A mass spectrometer has been used to analyze the vapors effusing from the orifice of a Knudsen cell containing pure and mixed alkali hydroxide condensed phases. Monomeric and dimeric species are detected in all cases except for LiOH in the temperature range 650–900°K. Thermochemical data are reported for the reactions $$2\mathrm{MOH}(\mathrm{g}\mathrm{)=}{\mathrm{M}}_2(\mathrm{OH}{)}_2(\mathrm{g}\mathrm{),}\mathrm{and}\hspace{0.17em}{\mathrm{M}}_2(\mathrm{OH}{)}_2(\mathrm{g}\mathrm{)+}{\mathrm{N}}_2(\mathrm{OH}{)}_2(\mathrm{g}\text{)=2}\mathrm{MN}(\mathrm{OH}{)}_2(\mathrm{g}\mathrm{),}$$ where M and N represent constituent alkali metals. The analogous behavior of the vaporization processes of alkali fluorides and hydroxides is discussed.