Trisodium EDTA in Aqueous Glycol Mixtures at Different\nTemperatures: A Volumetric and Ultrasonic Investigation

Polyethylene\nglycols 200 and 400 were subjected to four separate\ntemperature measurements for density and sound speed in a trisodium\nEDTA/water combination. According to this information, the following\nquantities were determined: limiting apparent molar volumes (ϕ<sub>V</sub><sup>0</sup>), apparent specific\nvolume (<i>v</i><sub>ϕ</sub>), isobaric molar thermal\nexpansion (α), isentropic compressibility (<i>k</i><sub>s</sub>), and limiting partial molar isentropic compression\n(ϕ<sub>K,s</sub><sup>0</sup>). In order to comprehend the molecular interactions and structural\ndifferentiation occurring within the mixture, the variations in these\nphysicochemical characteristics were examined as functions of concentrations\nas well as temperatures. In mixes with a high water content, the hydrophobic\nhydration process of glycols that were investigated became apparent.\nAdditionally, it was also determined how much the –CH<sub>2</sub>– and –O– groups contributed to the system’s\nvolume and acoustic characteristics. These contributions are applicable\nto a broad variety of data as the computed values using the group\ncontribution technique were in strong alignment during the observed\ndata. The combination has been the subject of FTIR spectroscopy studies,\nwhich reveal the intermolecular forces and the presence of hydrogen\nbonds within the ternary system.