XLIX. The adsorption of gases at high saturations I: The adsorption of nitrogen, argon and oxygen

Abstract

Abstract The adsorption of argon, nitrogen, and oxygen on an aluminium foil has been determined by a gravimetric method. The purpose of the investigation was to obtain data at high saturations for comparison with the Frenkel-Halsey-Hill equation describing multilayer adsorption. The isotherms obtained indicate that this equation is obeyed closely for the three gases. Apparent deviations in the case of argon and oxygen can be ascribed to anomalous packing in the first few atomic layers and allowance can be made for this effect. The verification is discussed in terms of the theoretical basis for the equation. Data is also given for the cross sections of the argon and oxygen molecules in the first atomic layer. It is suggested that these cross sections are considerably greater than values calculated from the corresponding bulk density. The magnitude of the standard nitrogen cross section is also discussed.