Study on thermodynamic properties of a double salt, K 2Mg(IO 3) 4·2H 2O

Abstract

The standard molar enthalpy of solution of double salts, K 2Mg(IO 3) 4·2H 2O(s), in water has been measured by solution calorimetry. From that value, combined with auxiliary values, the standard molar formation enthalpy has been derived: Δ f H m Θ (K 2Mg(IO 3) 4·2H 2O,s,298.2 K = −2510.69 kJ mol −1. The standard free energy {Δ f G m Θ (K 2Mg(IO 3) 4·2H 2O,s,298.2 K) = −2061.72 J K mol −1} and the absolute entropy ( S m Θ(K 2Mg(IO 3) 4·2H 2O,s,298.2 K) = 258.36 J K −1 mol −1 were also calculated.