ADSORPTION OF GASES ON BENZENE-PREPLATED GRAPHITE

We measured volumetrically adsorption isotherms of N-2, Ar, CH4, and K r on benzene-preplated graphite at 77 K. N-2 and Ar exhibit a new step on the isotherm at 5.0 and 4.3 Torr, respectively, suggesting some ph ase transition of the gases adsorbed on a single layer of benzene. On the other hand, CH4 and Kr shaw layerwise condensation transitions eve n when one monolayer of benzene is preadsorbed, implying that benzene is displaced by these gases, but to the smallest extent among those ob served previously for other systems. Benzene is also found to be solub le in N-2, Ar, and Kr.