Enthalpies of dilution of tris-ethylenediaminocobalt(III) chloride in aqueous solution at 25°C

Abstract

The enthalpies of dilution for aqueous solutions of [Co(en)3]Cl3, where en = 1,2-diaminoethane, have been measured at 25°C, and up to m = 1 mol-kg-1, using a new large isoperibol calorimeter by the >long-jump> method. Relative apparent molar enthalpies Lφ have been extracted as an empirical equation relating Lφ and m. Comparison with other 3:1 and 1:3 aqueous systems confirms the previously suggested hydrophobic character of the [Co(en)3]3+ cation.