M.SH ZAMANY - Department of Chemistry, Faculty of sciences, Islamic Azad university, Tehran, Iran
R TAHERY - Department of Chemical Engineering, Faculty of Engineering, Islamic Azad university, Tehran, Iran

The ther modynamic and transport properties of liquids and liquid mixtures have been used to understand the molecular interactions between th e component s of the mixture and also for engineeri ng applications concerni ng heat tran sfer, mass transfer, and fluid flow.O ne of the most strikin g demonst rations of t he intermolecular forces is the te nsion at the surface of a liquid.T he surfacetension (ƴ ), generally e mployed as a quantitati ve index of this tension, is defined as the force exerted in the plane of the surface per unit length (dynes/cm).additionally, surfa ce tension is equal to the change in the Gibbs e nergy in the process of formation of a unit area of the surface layers fr om molecules present i n the bulk of the liquid phase. there are different methods and theori esfor surface tension calculation but in this p aper we d ecided to use lampersk i model that have been applied already, but there is not an y report of this view that is calcula te with these binary solutions.[۱-۴]

Surface tension,Bina rysolution, Lamperski model, molecular interac tions.