Excess Volumes of Mixtures of Cycloalkanes and Methylcycloalkanes

Abstract Excess volumes v E have been obtained for mixtures of cyclopentane, methylcyclopentane, methylcyclohexane + n‐heptane, n‐decane, n‐tetradecane, carbon tetrachloride: methylcyclopentane + benzene, cyclopentane, cyclohexane, methylcyclohexane and methylcyclo‐hexane + cyclopentane at 293.15 K and 313.15 K, and cyclohexane + benzene at 293.15 K. The excess volumes of cyclopentane mixtures are much smaller than those of cyclohexane mixtures. Addition of a methyl group to cyclopentane enhances v E , to cyclohexane decreases v E . This behaviour seems to be caused by packing effects due to molecular structure, as yet not sufficiently accounted for by theories of mixtures.