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Statistical Thermodynamics. Lecture 1 : Thermodynamics review. Dr. Ronald M. Levy ronlevy@temple.edu. Chemical Physics: Statistical mechanics. Chemical Physics: explain microscopic properties based on the properties of individual molecules and molecular interactions.
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Statistical Thermodynamics Lecture 1: Thermodynamics review Dr. Ronald M. Levy ronlevy@temple.edu
Chemical Physics: Statistical mechanics Chemical Physics: explain microscopic properties based on the properties of individual molecules and molecular interactions Statistical Mechanics: Statisitical Mechanics Microscopic Macroscopic Atom Molecule Thermodynamics Themodynamics: Mathematical relation between experimental properties of macroscopic systems Isothermic compressibility coefficient volumetric thermal expansion coefficient MQ. Chapter 1 1
Thermodynamic Potential Thermodynamic Potential: The differential form of first law of thermodynamics dE = dQ – dW = TdS – pdV E (S, V) Thermodynamic Potential Independent Variable E (S, V) (S, V) Internal energy Helmholtz free energy A (T, V) (T, V) G (T, p) (T, p) Gibbs free energy H (S, p) (S, p) Enthalpy Done by Legendre transform 3
Legendre transformation Legendre Transforms: y(x) P2 = dy/dx @(x2,y2) P1 = dy/dx @(x1,y1) Ψ(P) y(x) Ψ1 Relation between the tangent and the intercept at any point on the function Ψ2 (intercept) How do we find the inverse Legendre transforms? 4
Application of Legendre transform Legendretransform 5
Maxwell Relations F Maxwell Relations and Thermodynamic square: V T Thermodynamic square S V V V T T E G Symmetric means + S P P S S T T P P P S H P Asymmetric means - G Gibbs free energy 1st Derivative Equation of state V S 2st Derivative Maxwell relations 6