The limiting molar partial enthalpies of mixing of iron, cobalt, nickel, palladium and platinum in liquid gallium and indium

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Gallium and indium have been used as solvents for the determination of the molar partial enthalpy of mixing Δ mix h m o(TM, Ga or In) (denoting liquid transition metal (TM) in infinite liquid gallium or indium) of the pure liquid transition metals Fe, Co, Ni, Pd and Pt by direct reaction calorimetry between 1000 K and 1500 K with the exception of Δ mix h m o(Fe, In) (because of the shape of its equilibrium phase diagram). All the limiting enthalpies listed below refer to the liquid state. With pure gallium as solvent, they correspond to the reaction TM(liq) − n Ga(liq) → TM 1Ga n (liq) at the experimental temperature T e, with n ⪢ 1. 1. (i) Δ mix h m o in gallium is found for Fe, Co, Ni, Pd and Pt to be −2, −44, −82, −144 and −155 kJ mol −1. 2. (ii) Δ mix h m o in indium is found for Co, Ni, Pd and Pt to be +28, −25, −127 and −114 kJ mol −1. In both solvents, these limiting enthalpies vary with a similar trend. This observation makes it possible to predict the limiting molar partial enthalpy Δ mix h m o(Fe, In) of mixing of iron in indium as +70 kJ mol −1. The results have been compared with the data proposed by Miedema and co-workers.