This study reports the measurements of solubility of crystalline molybdenum trioxide, MoO3, in NaClO4 solutions at 573.2 K and pressures, close to the saturation water vapor. In total, there are 16 data points at NaClO4 molalities between 0.005 and 2.21. The solubility is explained by two dissolution reactions: MoO3(cr) + H2O(l) = HMoO4 - + H+, and MoO3(cr) + H2O(l) = H2MoO4(aq). The solubility moderately increases with the sodium perchlorate concentrations. In our view, this effect can be fully explained by the variations of the activity coefficients of H+ and HMoO4 - in sodium perchlorate solutions, without the need to invoke a complex formation between Na+ and HMoO4 -, as was proposed in the literature. A better knowledge of speciation, association and thermodynamic properties of solutions of typical electrolytes (such as NaCl, NaClO4, etc) at elevated temperatures is a prerequisite for a more definite and precise interpretation of solubility data for solid compounds in high-temperature solutions.
Compounds
#
Formula
Name
1
MoO3
molybdenum oxide (MoO3)
2
ClNaO4
sodium perchlorate
3
H2O
water
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.