Integral molar enthalpies of mixing were determined by drop calorimetric method for Ag Ca liquid alloys at temperatures (1254 and 1131) K using a Setaram MHTC 96 Line evo calorimeter. Measurements were conducted for alloys of concentrations between 0.0642 6 XCa 6 0.9396 at T = 1254 K and at 1131 K between 0.7564 6 XCa 6 0.9647. The obtained values are negative in the entire range of concentrations and the minimum of the integral enthalpy of mixing equal 24609 J/mol of atoms was observed for 0.4634 mol fraction of calcium at T = 1254 K. The analysis of experimental data showed that most probably DHm of Ag Ca liquid alloys is independent of temperature and that they are almost twice less exothermic than those ones by the partial pressure measurements. Based on the data of this study and that available in the literature, the interaction parameters of Redlich Kister equation for the liquid Ag Ca phase were evaluated. The concentration fluctuation structure factor Scc(0) calculated using drawn up in this study equation showed the swallow minimum between Ca concentrations appropriate for Ag9Ca2 and AgCa intermetallic phases what can suggest at two kind of associates in liquid solutions.
Compounds
#
Formula
Name
1
Ag
silver
2
Ca
calcium
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.
Type
Compound-#
Property
Variable
Constraint
Phase
Method
#Points
POMD
1
2
Excess molar enthalpy (molar enthalpy of mixing), kJ/mol ; Liquid