版权所有：华东理工大学物理化学教研室 上一页 下一页 返回目录 Part 1: Equilibrium 9. Chemical equilibrium Bilingual Program
版权所有：华东理工大学物理化学教研室 上一页 下一页 返回目录 Part 1: Equilibrium 9. Chemical equilibrium Bilingual Program
版权所有：华东理工大学物理化学教研室 2 Spontaneous chemical reactions 9.1 The Gibbs energy minimum The response of equilibria to the conditions 9.2 How equilibria respond to pressure 9.3 The response of equilibria to temperature Applications to selected systems 9.4 The extraction of metals from their oxides 9.5 Acids and bases 9.6 Biological activity:the thermodynamics of ATP 9. Chemical equilibrium
版权所有：华东理工大学物理化学教研室 2 Spontaneous chemical reactions 9.1 The Gibbs energy minimum The response of equilibria to the conditions 9.2 How equilibria respond to pressure 9.3 The response of equilibria to temperature Applications to selected systems 9.4 The extraction of metals from their oxides 9.5 Acids and bases 9.6 Biological activity:the thermodynamics of ATP 9. Chemical equilibrium
版权所有：华东理工大学物理化学教研室 3 1) The reaction Gibbs energy ⇔ BA 9.1 The Gibbs energy minimum For the simplest possible chemical equilibrium Suppose an infinitesimal amount dξ of A turns into B: The change in the amount of A present is dnA = -dξ The change in the amount of B present is dnB = + dξ . The quantity ξ is called the extent of reaction; The dimensions is amount of substance, (moles)
版权所有：华东理工大学物理化学教研室 3 1) The reaction Gibbs energy ⇔ BA 9.1 The Gibbs energy minimum For the simplest possible chemical equilibrium Suppose an infinitesimal amount dξ of A turns into B: The change in the amount of A present is dnA = -dξ The change in the amount of B present is dnB = + dξ . The quantity ξ is called the extent of reaction; The dimensions is amount of substance, (moles)
版权所有：华东理工大学物理化学教研室 4 1) The reaction Gibbs energy The reaction Gibbs energy, ΔrG, is defined as the slope of the graph of the Gibbs energy plotted against the extent of reaction, ξ p,T ξ G G ⎟⎠⎞ ⎜⎝⎛ ∂∂ r =Δ At constant T、p, the change in Gibbs energy is G = μ n + μ ddd nBBAA = − A + Bdd ξμξμ = − AB )d( ξμμ r μμ AB ξ G G p,T ⎟ −= ⎠⎞ ⎜⎝⎛ ∂∂ =Δ 9.1 The Gibbs energy minimum
版权所有：华东理工大学物理化学教研室 4 1) The reaction Gibbs energy The reaction Gibbs energy, ΔrG, is defined as the slope of the graph of the Gibbs energy plotted against the extent of reaction, ξ p,T ξ G G ⎟⎠⎞ ⎜⎝⎛ ∂∂ r =Δ At constant T、p, the change in Gibbs energy is G = μ n + μ ddd nBBAA = − A + Bdd ξμξμ = − AB )d( ξμμ r μμ AB ξ G G p,T ⎟ −= ⎠⎞ ⎜⎝⎛ ∂∂ =Δ 9.1 The Gibbs energy minimum
版权所有：华东理工大学物理化学教研室 5 1) The reaction Gibbs energy As the reaction advances the slope of the Gibbs energy changes. Equilibrium corresponds to zero slope, at the foot of the valley. when μA> μB, , ΔrG<0 the reaction A →B is spontaneous; when μA < μB , , ΔrG>0 the reaction B →A is spontaneous; ΔrG = − μμ AB when ΔrG=0: The slop is zero and the reaction is spontaneous in neither direction. The composition of the reaction mixture at equilibrium 9.1 The Gibbs energy minimum
版权所有：华东理工大学物理化学教研室 5 1) The reaction Gibbs energy As the reaction advances the slope of the Gibbs energy changes. Equilibrium corresponds to zero slope, at the foot of the valley. when μA> μB, , ΔrG<0 the reaction A →B is spontaneous; when μA < μB , , ΔrG>0 the reaction B →A is spontaneous; ΔrG = − μμ AB when ΔrG=0: The slop is zero and the reaction is spontaneous in neither direction. The composition of the reaction mixture at equilibrium 9.1 The Gibbs energy minimum