Premium
Solubility of Water Vapor in Alkali Borate Melts
Author(s) -
FRANZ HELMUT
Publication year - 1966
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1966.tb13302.x
Subject(s) - solubility , alkali metal , boron , chemistry , vapor pressure , inorganic chemistry , lithium borate , potassium , lithium (medication) , molar solubility , evaporation , thermodynamics , borate glass , organic chemistry , medicine , physics , endocrinology
The solubility of water vapor at 750° to 1050°C was determined for alkali borate melts containing 0 to 40 mole % Li 2 O, Na 2 O, or K 2 O. In all cases the solubility in these melts is linearly proportional to the square root of the H 2 O partial pressure. At p H 2 O = 1 atm and T = 900°C, o.5 to 2.2 mole % H 2 O are dissolved in the melts in equilibrium. In the potassium borate melts a minimum of solubility was observed at about 25 mole % K 2 O; in the sodium borate melts the minimum was at 35 to 40 mole % Na 2 O. In the lithium borate melts a minimum of solubility was not reached in the range of compositions investigated. These results are discussed in terms of a concept for the acid‐base properties of melts and glasses in which the position of the solubility minimum corresponds to the “neutral point” of an acidity‐basicity scale. Some corroborating qualitative observations concerning the evaporation of components from the glass melts and the chemical resistivity of the corresponding solid glasses are discussed.