Abstract: | The standard enthalpies of formartion of crystalline -RbNbUO6, -RbNbUO6, and RbNbUO6·H2O at 298.15 K were determined. The temperature dependence of the heat capacity of -RbNbUO6, RbNbUO6·H2O, and -RbNbUO6 was studied in the range 60-300 K. The thermodynamic functions and equilibrium constants of the reactions involved in synthesis of rubidium uranoniobates at various temperatures were calculated. |