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Experimental densities, were experimentally determined at 298.15 K for the following mixtures: (i) Binary mixtures: Cyclohexane + n-hexane, cyclohexane + n-octane, cyclohexane + n-decane, cyclohexane + n-dodecane, cyclohexane + n- hexadecane, n-hexane + n-octane, n-hexane + n- octane, n-hexane + n-decane, n-hexane + n-dodecane, and n-Hexane + n-hexadecane. (ii) Ternary mixtures: n-hexane + n-octane + cyclohexane, n- hexane + n-decane + cyclohexane, n-hexane + n- dodecane + cyclohexane, n-hexane + n-hexadecane + cyclohexane. (iii) Quaternary mixtures: n-hexane + n-octane + n-dodecane + cyclohexane. From the experimental densities , the excess molar volumes of binary, ternary, and quaternary mixtures were calculated at 298.15 K. The Prigogine-Flory-Patterson theory successfully predicted the experimental excess molar volumes for binary mixtures studied here and indicates the importance of the three contributions to excess molar volumes: interactional, free volume, and internal pressure.

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