Densities of aqueous solutions of lithium sulfate (Li2SO4) and lithium trifluoromethanesulfonate (LiCF3SO3) at solute molalities ranging from 0.05 to 2.7 or 9.6 mol*kg 1, respectively, have been measured by vibrating-tube densimetry over the temperature range 293.15 = T/K = 343.15 at 0.1 MPa pressure. The apparent molar volumes (V) of Li2SO4(aq) and LiCF3SO3(aq) derived from these data were fitted using an extended Redlich Rosenfeld Meyer equation. The V? values for the two systems exhibit quite different dependences on concentration and temperature, as do the isobaric expansibilities. A combination of the present and literature data reveals that the densities for Li2SO4(aq) given in standard compilations are unreliable at low concentrations. Comparison of the present results with literature data for related salts shows that V(LinX) and V(NanX) exhibit a crossover at 0.5 mol*kg 1 for both systems, similar to those observed previously for other lithium and sodium salts. Consideration of an appropriate series of lithium salts suggests that anion size influences departures from the Debye Huckel limiting law for volumes, whereas for a series of sulfate salts cation size does not appear to be a major factor.
Compounds
#
Formula
Name
1
CF3LiO3S
lithium trifluoromethanesulfonate
2
Li2O4S
lithium sulfate
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.