Mutual diffusion, intradiffusion and viscosity coefficients for mixtures of cyclopentane and cyclooctane at 298.15 K

Abstract

Mutual diffusion, intradiffusion and viscosity coefficients have been measured at 298.15 K for the system cyclopentane (1)+cyclooctane (2). The mutual diffusion coefficient extrapolates to D^o₂₁ 2.361×10^-9 m s^-1 for pure cyclopentane and to D°₁₂ 0.793x 10^-9 m s^-1 for pure cyclooctane and these values are in good agreement with the corresponding tracer-diffusion ones. The viscosity and intradiffusion coefficients vary from 0.415 × 10^-3 kg m^-1 s^-1 and 3.114 × 10^-9 m² s^-1 for pure cyclopentane to 2.250 × 10^-3 kg m^-1 s^-1 and 0.546 × 10^-9 m² s^-1 for pure cyclooctane.    

It is shown that the intradiffusion and viscosity coefficients can be related through the Stokes-Einstein equation. The diffusion measurements have been transformed to velocity cross-correlation coefficients and it is found that there appear to be no special associative effects or structural features in this system.