This paper investigates the critical behavior of charged AdS black holes in an extended phase space, where the cosmological constant is treated as a thermodynamic pressure and its conjugate quantity as thermodynamic volume. The authors compare the thermodynamic properties of these black holes with those of the Van der Waals fluid, focusing on the critical point, which occurs at the divergence of specific heat at constant pressure. They calculate the critical exponents and show that they match those of the Van der Waals system, completing the analogy with the liquid-gas system. The study begins by reviewing the thermodynamic properties of the Van der Waals fluid, including its critical exponents and the behavior of its Gibbs free energy. The authors then analyze the thermodynamic properties of charged AdS black holes, identifying the thermodynamic volume and pressure, and deriving the equation of state for these black holes. They show that the behavior of these black holes in the extended phase space is analogous to that of the Van der Waals fluid, with similar critical exponents and phase transition behavior. The paper also discusses the Gibbs free energy of charged AdS black holes, showing that it exhibits a swallowtail behavior, indicating a first-order phase transition. The authors calculate the critical exponents for the black hole system and find that they match those of the Van der Waals fluid, confirming the analogy between the two systems. They conclude that treating the cosmological constant as a dynamical quantity in the extended phase space provides a more accurate description of the thermodynamic behavior of charged AdS black holes, and that this approach is a promising theoretical direction for further research.This paper investigates the critical behavior of charged AdS black holes in an extended phase space, where the cosmological constant is treated as a thermodynamic pressure and its conjugate quantity as thermodynamic volume. The authors compare the thermodynamic properties of these black holes with those of the Van der Waals fluid, focusing on the critical point, which occurs at the divergence of specific heat at constant pressure. They calculate the critical exponents and show that they match those of the Van der Waals system, completing the analogy with the liquid-gas system. The study begins by reviewing the thermodynamic properties of the Van der Waals fluid, including its critical exponents and the behavior of its Gibbs free energy. The authors then analyze the thermodynamic properties of charged AdS black holes, identifying the thermodynamic volume and pressure, and deriving the equation of state for these black holes. They show that the behavior of these black holes in the extended phase space is analogous to that of the Van der Waals fluid, with similar critical exponents and phase transition behavior. The paper also discusses the Gibbs free energy of charged AdS black holes, showing that it exhibits a swallowtail behavior, indicating a first-order phase transition. The authors calculate the critical exponents for the black hole system and find that they match those of the Van der Waals fluid, confirming the analogy between the two systems. They conclude that treating the cosmological constant as a dynamical quantity in the extended phase space provides a more accurate description of the thermodynamic behavior of charged AdS black holes, and that this approach is a promising theoretical direction for further research.