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We have measured the standard free energies and standard enthalpies of adsorption as well as saturated surface coverages for hexanoic acid and 1-propanol adsorbed at the air−aqueous interface of sodium chloride (NaCl) and ammonium sulfate ((NH₄)₂SO₄) solutions of concentrations between 0 and 4 mol L^-1. Temperature-dependent surface tension measurements are used to obtain ΔG⁰_aq→σ and ΔH⁰_aq→σ; using known Henry's law constants and estimated values of the salting-out coefficient we calculate the gas−interface adsorption parameters ΔG⁰_g→σ and ΔH⁰_g→σ. A small (∼1−2 kJ mol^-1) decrease in ΔG⁰_aq→σ with increasing salt concentration is accompanied by an increase (∼10−30%) in saturated surface coverage, consistent with the expected “salting-out” behavior. Adsorption from the gas phase becomes somewhat less favorable with increasing salt concentration for both organic species. The …