C. Huang and W.P. Cheng (J. Colloid Interface Sci. 188, 270 (1997)) examined the adsorption of the hexacyanoferrate(III) ion, [Fe(CN)₆]³⁻, on γ-Al₂O₃ from aqueous solution. They modelled the adsorption with a modified Langmuir isotherm, obtaining the following values of α at pH=6.5:

Determine the isosteric enthalpy of adsorption, Δ_adsH^⦵, at this pH. The researchers also reported Δ_adsS^⦵ =+146 Jmol⁻¹K⁻¹ under these conditions. Determine Δ_adsG^⦵.

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T/K 10-11α 283 2.642 298 2.078 308 1.286 318 1.085