Effects of sizes of nano-copper oxide on the equilibrium constant and thermodynamic properties for the reaction in nanosystem

Thermodynamic properties and equilibrium constant of reaction in nanosystems were analyzed theoretically. The effects of sizes of nano-CuO on thermodynamic properties and equilibrium constant were studied using the reaction of nano-copper oxide and sodium bisulfate as a system. The experimental results indicate that with the sizes of reactant decreasing, the molar Gibbs free energy (ΔrGm), the molar enthalpy (ΔrHm) and the molar entropy (ΔrSm) decrease, but the equilibrium constant (K) increases and there are linear trends between the reciprocal of sizes for nano-CuO and the values of ΔrGm, ΔrHm, ΔrSm and Ln K, which are in agreement with the theoretical analysis.

► Thermodynamic properties depend on the sizes of reactant in nanosystems.
► The equilibrium constant is also correlated to the sizes of reactant.
► With the sizes of reactant decreasing.
► Gibbs function, enthalpy and entropy decrease but the equilibrium constant increase.