Densities and Apparent Molar Volumes of Aqueous Solutions of Li2SO4 and LiCF3SO3 at Temperatures from 293 to 343 K

• DOI: 10.1021/acs.jced.6b00519
• Publication Date: 2016-09-14T19:56:27Z
• Authors: Bin Hu; Lubomir Hnedkovsky; Glenn Hefter
• Keywords: Trifluoromethanesulfonate; Lithium nitrate; Isobaric process; Debye–Hückel equation; Lithium sulfate; Limiting

Densities of aqueous solutions lithium sulfate (Li2SO4) and 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 0.1 MPa pressure. The apparent molar volumes (Vϕ) Li2SO4(aq) LiCF3SO3(aq) derived these data were fitted using an extended Redlich–Rosenfeld–Meyer equation. Vϕ values for two systems exhibit quite different dependences on concentration temperature, as do isobaric expansibilities. A combination present literature reveals that densities given in standard compilations are unreliable low concentrations. Comparison results with related salts shows Vϕ(LinX) Vϕ(NanX) a crossover ≈0.5 mol·kg–1 both systems, similar those observed previously other sodium salts. Consideration appropriate series suggests anion size influences departures Debye–Hückel limiting law volumes, whereas cation does not appear be major factor.