Thermodynamic study of alkali sulphates: Calculation of enthalpy,entropy and Gibbs free energy

Joined with measures of specific heat at low temperature , a calorimetric study of alkali sulphates from ordinary temperature to 1500 K has allowed the calculation of enthalpy, entropy and Gibbs free energy of these salts. The value of entropy at melting point is compared with the value assessed by an acoustical method.