Densities, Refractive Indices and Ultrasonic Speeds of N,N-dimethylformamide + Acetone Binary Mixtures at Different Temperatures

Abstract

Experimental densities, ρ, refractive indices, n, and ultrasonic speeds, u, at various compositions and at various temperatures from (298.15 to 313.15) K for N,N-dimethylformamide + acetone binary mixtures were measured. From these results excess molar volumes (Formula presented.), deviations in refractive indices (Δn), isentropic compressibilities (Δks), partial molar volumes (Formula presented.), and partial molar compressibilities (Formula presented.), of acetone in N,N-dimethylformamide were calculated. All the excess and deviation functions were fitted to Redlich–Kister polynomial equation to determine the fitting coefficients and the standard deviations. The values of (Formula presented.) and Δks showed negative deviations, whereas excess Δn showed positive values over the entire range of concentrations and temperatures. The observed variations of these parameters, with concentration and temperature are discussed in terms of the intermolecular interactions and structural effects between the unlike molecules of the binary mixtures.