Page 11 - Bruno Linder Elementary Physical Chemistry

August 19, 2010 10:36 9in x 6in b985-fm Elementary Physical Chemistry

x Elementary Physical Chemistry

2.11. Enthalpy Changes in Chemical Reactions . . . . . . . 18
2.12. Standard Enthalpy .. ... .. .. ... .. .. ... . 18
2.13. Variation of Enthalpy with Temperature . . . . . . . . 19

3. The Second Law of Thermodynamics 20
3.1. Statements of the Second Law . .. ... .. .. ... . 21
3.2. Carnot Cycle . .. .. ... .. .. ... .. .. ... . 22
3.3. Engine Efficiency . .. ... .. .. ... .. .. ... . 22
3.3.1. Reversible Process . .. .. ... .. .. ... . 24
3.3.2. Irreversible Process . . . . . . . . . . . . . . . 25
3.3.3. General Changes in Entropy . . . . . . . . . . 26
3.3.4. Isolated Systems . . . . . . . . . . . . . . . . . 27
3.4. Determination of Entropy . .. .. ... .. .. ... . 27
3.4.1. Entropy change in Phase Transitions
(solid–liquid, liquid–vapor, solid–vapor) . . . . 27
3.4.2. Entropy change in (Ideal) Gas Expansion . . . 28

4. The Third Law of Thermodynamics 29

4.1. Standard Entropy . .. ... .. .. ... .. .. ... . 30
4.2. Molecular Interpretation of Entropy .. .. .. ... . 30
4.3. The Surroundings . . . . . . . . . . . . . . . . . . . . . 31
4.4. The Entropy of the Surroundings . . . . . . . . . . . . 32

5. The Free Energy Functions 33
5.1. The Gibbs Free Energy ... .. .. ... .. .. ... . 33
5.2. Free Energy Changes in Chemical Reactions . . . . . . 35
5.3. Variation of G with T and P . .. ... .. .. ... . 37
5.4. Generalization of the Free Energy. Activity . . . . . . 37
5.5. Partial Molar, Molal Quantities . . . . . . . . . . . . . 38
5.6. The Chemical Potential .. .. .. ... .. .. ... . 39
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5.7. Relation of ∆G to the Equilibrium Constant, K .. . 40
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5.8. Variation of K with T ... .. .. ... .. .. ... . 41
6. Phase and Chemical Equilibria 43
6.1. Phase Equilibrium . . . . . . . . . . . . . . . . . . . . 43
6.1.1. The Phase Rule .. .. .. ... .. .. ... . 43
6.1.2. The Clapeyron Equation . . . . . . . . . . . . 44