Viscosity of Associated Liquids

Abstract

EXISTING theories of the viscosity of liquids fail to give a satisfactory account of the temperature variation of the viscosity of certain associated liquids. The X-ray diffraction patterns of liquids show that the inter-atomic distances vary about a mean; the variability increasing with increasing temperature. In addition, for the silicate glasses and for water, it is concluded that the structure is a random three-dimensional network of atomic bonds. This network is continuous throughout the liquid and in this sense glasses and water are associated liquids. In glasses the network is built up of Si—O bonds and in water of O—H bonds, the silicon atoms being surrounded by four oxygen atoms, and in water, the oxygen atoms by four hydrogen atoms.