Volumetric and ultrasonic study of polyethylene glycols in aqueous solutions of niacin at different temperatures

Significant information regarding the molecular interactions in the ternary solution consisting of Vitamin B-3 (Niacin), water and polyethylene glycols (PEG 200/PEG 600) are attained from the calculated volumetric and acoustic parameters. Initially, the density (rho) and speed of sound (c) for polyethylene glycols (0.1 to 0.5) mol.kg(-1) in aqueous niacin (0.01, 0.02, and 0.03) mol.kg(-1) were measured under 0.1 MPa pressure as a function of temperature at (293.15-308.15) K. Utilizing the experimental density values, the apparent Molar Volume (V-phi), Partial Molar Volume (V-phi(0)) and Partial Molar Volume of transfer (Delta V-phi(0)) are calculated and the apparent Molar Isentropic compression (K-phi,K-S), Partial Molar Isentropic compression (K-phi,S(0)) and Partial Molar Isentropic compression of transfer (Delta K-phi(0)) are estimated using the speed of sound. The empirical constants a, b, and c along with the pair and triplet coefficients (V-AB,V-ABB,K-AB, K-ABB) are calculated. (C) 2020 Elsevier Ltd.