The molar enthalpies of solution and vapour pressures of saturated aqueous solutions of aluminium chloride, aluminium nitrate and aluminium sulphate

摘要

Vapour pressures of water over saturated solutions of aluminium chloride, aluminium nitrate and aluminium sulphate were determined as a function of temperature. The vapour pressures served to evaluate the water activities, osmotic coefficients and molar enthalpies of vaporization. Molar enthalpies of solution of aluminium chloride hexahydrate, DELTA_(sol)H_m (AlCl_3·6H_2O, T = 295.02 K, m = 0.02084 mol·kg~(-1)) = -(54.6 +- 2.1) kJ·mol~(-1), aluminium nitrate nonahydrate, DELTA_(sol)H_m (Al(NO_3)_3·9H_2O; T = 296.62 K, m = 0.01342 mol·kg~(-1)) =-(30.7 +- 1.0) kJ·mol~(-1) and aluminium sulphate octadecahydrate, DELTA_(sol)H_m(Al_2(SO_4)_3·18H_2O, T = 297.60 K, m = 0.00756 mol·kg~(-1)) = -(46.4 +- 2.5) kJ·mol~(-1), were determined calorimetrically.