Propiedades volumétricas detrifluorometanosulfonato de 1- etil-3-metilimidazolio en solución acuosa de tiosulfato de sodio pentahidratado a diferentes temperaturas

Abstract

Densities of pseudobinary mixture of water + 1-ethyl-3-methyl-imidazolium trifluoromethanesulfonate ([Emim+][CF3SO3-]) + aqueous solution of sodium thiosulfate pentahydrate (Na2S2O3.5H2O) were experimentally determined at temperatures from 283.15 to 318.15 K, using an Anton Paar model DMA 5000 vibrating tube densitometer. From these data the apparent molar volumes(∅ 0), limiting apparent volumes (∅ 0) and standard volumes of transfer (Δtr∅ 0) were calculated. The limiting apparent molar volume was correlated with the temperature leading to a negative second derivative of the limiting apparent molar volume respect to the temperature. This fact could indicate that [Emim+] [CF3SO3 -] behaves as a solute capable of braking the solvent structure, while the positive value for Δtr∅ 0 could indicate the prevalence of ion-ion interactions in the solution, which confirms the results of Hepleŕs criterion.