Partial enthalpies of titanium, hafnium, tantalum, tungsten and iridium inliquid tin at high dilution

The partial enthalpies of titanium, hafnium, tantalum, tungsten and iridium in liquid tin at 1173K were measured at high dilution by direct reaction c alorimetry (drop method) with the help of a Tian-Calvet high-temperature ca lorimeter. When referred to liquid metals we found h(Ti)/kJ.mol(-1) = 106.3 - 25.6 x(Ir), h(Hf)/kJ.mol(-1) = 87.3 + 29.1 x(Hf) , h(Ta)/kJ.mol(-1) = 102.7 - 9.6 x(Ta), h(w)/kJ.mol(-1) = 94.9 - 58.2 x(w) and h(Ir)/kJ.mol(-1) = -111.2 - 12.4 x(I r). The limiting partial enthalpies were deduced by extrapolation to infinite d ilution. (C) 1999 Elsevier Science S.A. All rights reserved.