Temperature Dependence of the Speed of Sound, Densities, and Isentropic Compressibilities of Hexane + Hexadecane in the Range of (293.15 to 373.15) K

The speed of sound u and density ρ for the binary mixture hexane + hexadecane has been measured as a function of composition and temperature along the saturation line between 293.15 K and 373.15 K. The speed of sound was measured by a pulse-phase echo ultrasonic device at a frequency of (1 to 5) MHz with an uncertainty of ±0.1%. The density was measured by an Ostwald−Sprengel-type pycnometer with an uncertainty of ±3 × 10-5 g·cm-3. The experimental results were used to calculate deviations of the speed of sound Δ u, excess molar volume V E, and isentropic compressibility k S . The values Δ u and V E were fitted by the Redlich−Kister equation.