Journal of Applied Sciences1812-56541812-5662Asian Network for Scientific Information10.3923/jas.2004.43.47Shahbazi-MoghaddamMorteza 1200441The purpose of present study was to apply a classical model for solid study. In the proposed model atoms were considered as points of mass having small oscillations near their equilibrium positions. Based on this consideration, the partition function was solved and with regard to equipartition theorem, its simplified equation has also been achieved. The model was applied to solid and necessary work for compressing solid, in order to obtain the compressibility factor as a function of solid volume and the temperature, has been calculated. A literal expression for pressure applied to solid and also an expression showing the compressibility variation have been deduced. For numerical application, aluminum was chosen as a solid in order to find out its parameters. The model can also easily be applied to other metals]]>Graudire, N.,1989Teyssier, J.L. and H. Brunet,1992pp: 43-48pp: 43-48