ULTRASONIC SPEEDS AND ISENTROPIC COMPRESSIBILITIES OF (1,4-DIOXANE + NORMAL-HEPTANE OR NORMAL-DECANE OR NORMAL-TETRADECANE)

Ultrasonic speeds u in {xOCH2CH2OCH2CH2 + (1 - x)n-CmH2m + 2} for m = 7, 10, and 14 were measured over the whole composition range and at 298.15 K by a pulse-echo-overlap technique of fixed-path type at a frequency of 2.25 MHz. Isentropic compressibilities κS and corresponding excess functions uE and κSE, together with Δu values, have been obtained for all measured mole fractions. The κSE values are negative for m = 7 and positive for m = 10 and 14 (the opposite is true for uE), while the Δu values are negative for the three measured mixtures. At 298.15 K all the studied properties have a "normal" behaviour with composition. © 1990.