The vapour pressures of saturated aqueous solutions of magnesium, calcium, nickel and zinc acetates and molar enthalpies of solution of magnesium, calcium, zinc and lead acetates

摘要

Vapour pressures of water over saturated solutions of magnesium, calcium, nickel and zinc acetates were determined as a function of temperature. The vapour pressures served to evaluate the water activities, osmotic coefficients and molar enthalpies of vapor- ization. Molar enthalpies of solution of magnesium acetate tetrahydrate, ~soIHm(T = 294.71 K;m=0.01 mol.kg-I)=-(15.65 +-0.97) kJ.mol-l; calcium acetate, ~soIHm(T =297.18 K; m=0.01 mol. kg~(-l))=-(28.15+-0.28) kJ .mol-l; zinc acetate dihydrate, ~soIHm(T = 297 .36 K; m = 0.01 mol. kg~(-1) ) = -(22.49 +-0.90) kJ .mol~(-l) and lead acetate trihydrate, ~sol Hm (T = 297.36 K; m = 0.0086 mol. kg~(-l) ) = (22.46+-0.94) kJ .mol-l, were determined calorimetrically.