Speeds of sound and isentropic compressibilities of (n-heptanol + n-pentane, or n-hexane, or n-heptane, or n-octane) at T = 303.15 K, and of (n-heptanol + 2,2,4-trimethylpentane) at T = 293.15 and 303.15 K

Speeds of sound u have been measured in binary liquid mixtures of n-heptanol (n-C7H15OH) and n-pentane (n-C5H12), or n-hexane (n-C6H14), or n-heptane (n-C7H16), or n-octane (n-C8H18) at T=303.15 K and in binary liquid mixtures of n-heptanol and 2,2,4-trimethylpentane (2,2,4-(CH3)3C5H9) at T=293.15 and 303.15 K. The values of u have been used to calculate the apparent excess speeds of sound Δu and the isentropic compressibilities KS for these mixtures. The excess isentropic compressibilities KSE have also been calculated from the values of KS. The KSE property has been found to be negative throughout the entire composition range for {x n-C7H15OH+(1−x)n-C5H12}, {x n-C7H15OH+(1−x)n-C6H14}, {x n-C7H15OH+(1−x)n-C7H16}, and {x n-C7H15OH+(1−x)2,2,4-(CH3)3C5H9}. For {x n-C7H15OH+(1−x)n-C8H18, the KSE has been found to be positive at very low mole fractions of n-C7H15OH, and negative at other mole fractions. The values of Δu and KSE have been fitted to representative equations.