Sayed Mostafa Hosseini - Department of Chemistry, College of Sciences, Shiraz University, Shiraz, Iran
Mohammad Mehdi Papari - Department of Chemistry, Shiraz University of Technology, Shiraz, Iran
Jalil Moghadasi - Department of Chemistry, College of Sciences, Shiraz University, Shiraz, Iran

The technique of perturbation modelling uses references values for systems that are similar enough to the system of interest that good estimates of desired values can be made with small corrections to the reference values. The most common reference now is that of Carnahan and Starling(CS)[1].In this work a perturbed hard-sphere equation of state has been developed to predict volumetric behaviour of several classes of fluids includingAr,CO2,R134a,H2O,Li and Na in a broad range of temperatures and pressures.