The present research work is concerned with the thermophysical
properties of tripotassium citrate and sodium benzoate in aqueous
(0.10, 0.15, and 0.20) mol·kg–1 1-ethyl-3-methylimidazolium
ethyl sulfate solutions at temperatures ranging (293.15–313.15)
K and 101.3 kPa pressure. The experimentally acquired density, sound
speed, and viscosity data have been employed to determine numerous
densimetric, acoustic, and viscometric parameters including the apparent
molar volumes (V
ϕ), partial molar
volumes at infinite dilution (V
ϕ
0), limiting apparent molar
expansibilities (E
ϕ
0), apparent molar isentropic compressibilities
(K
ϕ,s), transfer properties, hydration
number (n
H), viscosity B-coefficients, and thermodynamic parameters of viscous flow (Δμ1
0, Δμ2
0, ΔH
2
0, and TΔS
2
0). The above-mentioned parameters
have been evaluated for the examination of interactions that are prevailing
among tripotassium citrate/sodium benzoate and 1-ethyl-3-methylimidazolium
ethyl sulfate in an aqueous medium. In addition, UV spectral analysis
was used for the examination of interactions existing among the considered
systems. Furthermore, the band gaps between the highest occupied molecular
orbital and the lowest unoccupied molecular orbital for the studied
systems and the interaction characteristics have been calculated using
density functional theory. The obtained results inferred the predominance
of the hydrophilic–hydrophilic interactions in the systems
under investigation.