In this paper, we investigate the thermodynamic characteristics of a viscous fluid called viscous variable Chaplygin gas (VVCG) model. The equation of state p=-B/ρ is used, with B=B_0 V^(-n/3) and B_0, a positive universal constant. Our study has also taken consideration of the bulk viscosity coefficient, ξ=ξ_0 ρ^(1/2). In order, to analyze the nature of the universe, the behavior of physical parameters in viscous fluid is discussed. The third law of thermodynamics validity is examined using the specific heat formalism. Furthermore, the thermal equation of state is discussed with the aid of thermodynamic entities. Adiabatic, specific heat, and isothermal conditions from classical thermodynamics are used to investigate thermodynamic stability.
