EMPIRICAL DEPENDENCES OF THE STANDARD ENTHALPY OF FORMATION FOR RELATED INORGANIC-COMPOUNDS ENHANCING GLASS FORMERS

For the double oxides and other related double A(x)B(y)C(z) compounds in the system AC-BC, linear correlations have been observed between st andard enthalpies of formation of the double compounds A(x)B(y)C(z) fr om the component compounds AC and BC (Delta H-f,cc(0) in kJ (g-atom)(- 1) and values of the sum of the molar fraction enthalpies of the compo nent compounds AC and BC (<Delta (H)over bar (0)(f)> = x(AC)Delta H-f( 0)(BC), in kJ (g-atom)(-1). In general, the dependence of H-f,cc(0) = f(<Delta (H)over bar (0)(f)>) has a minimum, its branches being descri bed with the help of linear equations (the average deviation from the known Delta H(f,cc)0 +/-47% values was less than +/-4.7% for 121 doubl e compounds in 34 systems). A conclusion has been drawn that these reg ularities (linear approximation rule-LAR) are characteristic for diffe rent types of inorganic double compound.