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 1771.    KINGTON, G. L., BEEBE, R. A., POLLEY, M. H., AND SMITH, W. R.  Entropy of Adsorbed Molecules.  Jour. Am. Chem. Soc., vol. 72, 1950, pp. 1775-1781; Chem. Abs., vol. 44, 1950, p. 6228.

        Differential heats of adsorption of N₂ and O₂ on TiO₂ were determined calormetrically at 78.5° K.  The TiO₂ used in both cases was a sample of anatase with a Brunauer, Emmett, and Teller (abs. 389) surface area of 13.9 m.² per gm.  The magnitude of the heat in both cases indicates that the adsorption is van der Waals in nature.  The initial increments of N₂ showed a heat of adsorption approximately 1 kcal. per mol. higher than the initial O₂ values.  The partial molal entropy of the adsorbed gas was determined from experimental data for both N₂ and O₂ adsorbed on C black and TiO₂ (anatase) at 78.5° K.  The results show that the partial molal entropy of the adsorbed gas is less than the partial molal entropy of the bulk 3-dimensional liquid or solid phases, at coverages less than a monolayer, as defined by B.E.T. v_m, for all the systems investigated.  At coverages greater than a monolayer, the partial molal entropy approaches the entropy of the 3-dimensional liquid or solid.  The entropy requirements of the B.E.T. theory are shown to be incompatible with experimental evidence at coverages less than a monolayer.

        KINI, K. A.  See abs. 1192, 1193, 1193a.