A Study of the Acid-Base Properties of Melts in the Na_2O-B_2O_3-SiO_2 System:I.Composition Joins with a Na_2O Content of Less Than 20 mol%

摘要

Three composition joins in the Na_2O-B_2O_3-SiO_2 system at constant Na_2O contents of 5,10, and 15 mol% are studied by the high-temperature method of determining oxygen ion exponents pO for oxide melts. It is found that the basicity of melts increases in going from the binary sodium borate system to the sodium silicate system. The acid-base properties of ternary melts are simulated under the assumption that their basicity is determined by the interaction in pseudobinary systems. It is shown that the basicity of the studied melts is governed, to a large extent, by the formation of the Na_2O.B_2O_3.2SiO_2 ternary compound.