Equilibrium and Kinetics

1. Equilibrium and Kinetics Chapter 2

2. Fig. 2.1

3. Fig. 2.2 unstable Activation barrier metastable stable

4. Otherwise UnstableMinimum Energy – STABLE EQUILIBRIUMMaximum Energy – UNSTABLE EQUILIBRIUMGlobal Minimum - Most STABLELocal Minimum - METASTABLE

5. Intensive Properties Pressure Temperature Extensive Properties Internal Energy E Enthalpy H = E + PV Eqn. (2.3)

6. Gibbs Free Energy (2.6) Condition for equilibrium ≡ minimization of G Local minimum ≡ metastable equilibrium Global minimum ≡ stable equilibrium

7. G = GfinalGinitial (2.7) G = 0  reversible change G < 0  irreversible or spontaneous change (2.8) G > 0  impossible

8. Josiah Willard Gibbs

9. Atomic or statistical interpretation of entropy

11. Boltzmann’s Tomb Central Cemetery, Vienna, Austria

12. Boltzmann’s Epitaph (2.5) W is the number of microstates corresponding to a given macrostate

13. (2.9) N=16, n=8, W=12,870

14. Stirling’s Approximation (2.11) 100!=

15. (2.10) (2.12)

16. Thermal energy Average thermal energy per atom per mode of oscillation is kT Average thermal energy per mole of atoms per mode of oscillation is NkT=RT (2.13)

17. Maxwell-Boltzmann Distribution (2.14) Fraction of atoms having an energy  E at temperature T

18. Svante Augustus Arrhenius 1859-1927 Nobel 1903 KINETICS (2.15)

19. ln (rate) Fig. 2.4

20. A + BC AB + C A + BC (ABC)* AB + C

21. (ABC)* Free Energy ΔG* A + BC AB + C Configuration

22. The three laws of thermodynamics First Law: You cannot win, you can only break even. Second Law: You can break even only at absolute zero. Third Law: You can’t reach absolute zero.