Viscosity and Surface Tension of Saturated n-Pentane

Light scattering by thermally excited capillary waves on liquid surfaces or iInterfaces can be used for the investigation of viscoelastic properties of fluids. In this work, the simultaneous determination of surface tension and liquid kinematic viscosity of n-pentane by surface light scattering (SLS) on a gas–liquid iInterface was carried out. The experiments are based on a heterodyne detection scheme and signal analysis by photon correlation spectroscopy (PCS). Measurements were performed under saturation conditions over a wide temperature range from about 233 to 363 K. For the whole temperature range the total uncertainty of the liquid kinematic viscosity and surface tension is estimated to be better than 1.0 and 1.2%, respectively. The results obtained corroborate the reliability of the SLS technique for the determination of thermophysical properties.