Learning outcomes of the course unit
The aims of the course are the following:
to establish and to develop the principles for the explanation and the interpretation of chemical reactions, by means of models, peculiarity of the Physical Chemistry;
to provide knowledge of thermodynamics and kinetics, especially with regard to the study and the interpretation of biochemical and biological processes;
to show that thermodynamics is the foundation for understanding the main machinery related to food preservation;
to give an outline of colloidal chemistry, foundation of structural and functional features of foods.
No preliminary examinations are requested, but it is recommended to attend the courses of General Chemistry, Physics and Mathematics before the course of Physical Chemistry.
Course contents summary
1. Equilibrium thermodynamics applied to chemical and biological systems with a statistical thermodynamics outline. Variables and state functions. The laws of thermodynamics. The temperature and pressure dependence of thermodynamic quantities. Thermochemistry. Calorimetry.. Outline of statistical Thermodynamics. Exercises.
2. Changes of state: physical transformations of pure substances. Phase diagrams. Clapeyron and Clausius-Clapeyron equations. Vapour-liquid phase transition and critical phenomena. The principle of corresponding states. Gibbs phase rule
3. Changes of state: physical transformations of simple mixtures. Open systems and partial molar quantities. Ideal and real solutions. Raoult and Henry laws. Fugacity and activity. The water activity in foods. Regular solutions. Ideal mixing and excess functions. Phase equilibria in binary systems. Fractional distillation. Azeotropes, eutectic, partially miscible liquids, binary mixtures compounds forming. Solvent chemical potential. Colligative properties. Osmotic pressure. Molecular weight measurements. Membrane equilibria. Solutions of macromolecules. Dialysis equilibrium. Donnan equilibrium. Transport phenomena: passive and active transport.
4. Equilibria of chemical reactions. Thermodynamics of chemical equilibrium. Gibbs free energy and equilibrium constant. Activity and ionic strength. Standard state. Distribution diagrams. Binding curves. Cooperativity.
5. Electrochemistry. Electrochemical cells. Electrodes. Nernst equation. Standard reduction potentials. The potentiometer.
6. Chemical kinetics. The rate of chemical reactions. Stoichiometry, order and , molecularity. 1st and 2nd order reactions. Half-life time. Arrhenius equation. Catalysis.
7. Intermolecular forces. Van de Waals forces. Dipole and induced dipole. Potential energy. Lennard-Jones potential. Hydrogen bond. Hydrophobic interactions. Partition coefficient.
8. Colloid chemistry. Dispersed systems. Size and shape of colloidal particles. Ostwald classification. Surface tension. Intermolecular forces in colloidal systems. DLVO theory. Structure and classification of surfactants. Micelle formation. Emulsions. Emulsifiers and stabilizers in foods. Microemulsions. Lyotropic and thermotropic liquid crystals.
- P. W. Atkins, Elementi di Chimica Fisica, seconda edizione, Zanichelli, Bologna, 2000
- A. Schiraldi, , Elementi di Chimica Fisica, Cisalpino, Milano (1993)
- A. Immirzi, Chimica Fisica (Termodinamica), CUES, Salerno (2002)
- Laidler, Meiser, Chimica Fisica, Editoriale Grasso, Bologna, 1999
Lectures by means of transparencies and/or computer presentations, available t
the students before classes.
Examination modalityDuring teaching activity (about two months) the students can take two written “in itinere” tests, one each month or, otherwise, there are written examinations on the whole syllabus during normal examination sections.