Viscosity and Chemical Constitution

SURFACE tension, σ and viscosity, η, are regarded as manifestations of van der Waals' intermolecular forces of attraction. If, therefore, rise in temperature merely separates the molecules of a liquid, n should be proportional to η½, since o is expressed in force units per cm. and η per cm. 2 . This is approximately true for unassociated liquids over a considerable temperature range from the boiling point downwards.