Chemical Sciences

FABIO RAMONDO
OLGA RUSSINA

The course aims to teach theoretical knowledge and laboratory skills related to the study of systems and processes from a thermodynamic point of view. Therefore, theoretical models for the study of equilibrium systems will be developed and the related demonstrations will be discussed. Furthermore, laboratory experiments related to some thermodynamic topics will be carried out, in order to consolidate the theoretical knowledge and acquire the ability to elaborate experimental data.
At the end of the course, as regards essential knowledge, the student must have acquired skills regarding the general principles of thermodynamics and the chemical-physical properties of gas, liquid, solid and solutions systems. In particular, it will have to know the thermodynamic quantities involved and their physical significance at the macroscopic level. The thermodynamic aspects of a process must be clearly understood. The student is expected to have the ability to: i) discern the thermodynamic aspects from the kinetic aspects among those that govern events; ii) select the equations and formulas most suitable for solving quantitative problems; iii) to understand how to measure a thermodynamic quantity (Dublin descriptors 1 and 2).
Laboratory experiences with related reports and classroom exercises are expected to be able to convey to the student the logical approach to the problems, the ability to synthesize and communicate the learned concepts with appropriate language (descriptors of Dublin 3 and 4) . Through the laboratory experiences and continuous references, made in the lectures, to phenomena that are daily manifested in human life, it will be provided solid scientific bases for the understanding of processes that take place in various areas and for their independent deepening by the student (Dublin descriptor 5).

The student acquires the principles of thermodynamics and chemical kinetics that allow to interpret and quantitatively predict the properties and reactivity of pure substances and binary mixtures as a function of physical and chemical conditions. The student is introduced to the applications of thermodynamics by solving simple applicative problems. In the laboratory the student experimentally verifies what is illustrated during the lessons and learns how to handle the collected data and how to write a report accompanied by graphs and numerical data analysis.

For a better learning of the topics proposed in this course, basic skills of Chemistry (inorganic chemistry, the periodic table of the elements, the concept of mole, kinds of concentrations, balancing chemical equations, balancing redox reactions, law of mass action, colligative properties, pH, basic background of electrochemistry). In addition, the student should be familiar with the basic knowledge of mathematics (derivatives and partial derivatives, differentials, simple integrals and differential equations, study of functions).

The first law of thermodynamics.
Definition of a thermodynamic system. States and properties of the systems. State functions and thermodynamic state. Thermal, mechanical and chemical equilibrium. Reversible and irreversible processes. Reversible work. The first law of thermodynamics: the formulation, heat, work, internal energy and its changes in the thermodynamic processes. Heat capacity, enthalpy, its changes in the chemical reactions and dependence on the temperature. Thermochemistry.

The second law of thermodynamics.
Irreversibility of natural events and entropy as a measure of irreversibility of thermodynamic transformations. Clausius inequality. Thermodynamic temperature. Changes of entropy in different conditions. The statistical view of the entropy. Boltzmann equation. Entropy change in the phase transitions. Mixing entropy. Temperature and its measurement.

The third law of thermodynamics.
Nernst theorem and Planck statement. Absolute entropy and its evaluation.

Thermodynamic equilibrium.
Thermodynamic potentials; Gibbs and Helmholtz free energy. Phase transitions. Phase diagrams for pure materials. Fugacity and activity, and chemical potential of pure gases, liquids and solids.

Multi-components systems.
Chemical potential, partial molar quantities, Gibbs-Duhem equation: fugacity and activity, Solutions and their properties: osmotic pressure, freezing point lowering, boiling point raising. Ideal solutions and regular solutions. Experimental methods to determine the partial molar quantities. Phase rule.

Chemical equilibrium.
Chemical reactions. Chemical equilibrium, thermodynamic constant and its dependence on temperature. Equilibrium electrochemistry: electrochemical potential, ions, ion activity, electrodes, electrochemical cells, standard electrode potential, electromotive force. Work in chemical reactions. Thermodynamic functions from electromotive force measurements. Theories of ionic solutions: Debye-Hückel theory (outline).

Chemical kinetics.
The rate of chemical reactions. Order, molecularity and mechanism of a reaction. Kinetics of consecutive reactions, steady-state kinetics, kinetics of reversible and irreversible. The temperature dependence of the rate of chemical reactions. Experimental methods to measure the rate of a chemical reaction. Catalysis. Homogeneous catalysis. Enzymatic kinetics: kinetics of Michaelis-Menten. Heterogeneous catalysis (outline)

Experimental activities
1. Measurement of the combustion heat of benzoic acid.
2. Measurement of heat capacity of metals.
3. Thermodynamic data of a chemical reaction by measurements of electromotive force as a function of temperature.
4. Determination of partial molar volumes by measurements of density of aqueous solutions.

There is no reference text. Some are suggested:
1. D. Gozzi Termodinamica Chimica, Edizioni Nuova Cultura
2. P. W. Atkins, J. de Paula - Chimica Fisica, Zanichelli
3. Notes on practical experiences written by Prof. Daniele Gozzi:
https://www.chem.uniroma1.it/sites/default/files/allegati_insegnamento/dispense%20labChimFis.pdf
4. Notes on Chemical Kinetics written by Prof. Guido Gigli:
https://www.chem.uniroma1.it/sites/default/files/allegati_insegnamento/cinetica_chimica.pdf

To deepen some topics:
1. E. Fermi Termodinamica, Boringhieri (available at the library G. Illuminati of Chemistry Department)
2. G. N. Lewis, M. Randall Termodinamica, Leonardo Edizioni Scientifiche (per approfondimenti) (available at the library G. Illuminati of Chemistry Department)

The course is composed of eighty hours, sixty-eight of which are devoted to the theoretical treatment of the topics proposed in the program (theoretical models, mathematical proofs, applications and limits of the obtained equations) and numerical exercises focused on thermodynamics and kinetics while the remaining twelve will be used to laboratory experiences where the student will carry practical experiences, the results of which have to be described and discussed in a report.

Laboratory attendance is mandatory.

The student will be evaluated by a written and oral exam in which the student should discuss one of the laboratory experiences (theoretical principles, materials, methods, processing of experimental data and results), some thermodynamic and kinetic issues with the relative proofs, and solve some numerical exercises. The capability of analysis, making judgment and communication skills will be also evaluated. Simple systems will be discussed to evaluate the student skills to frame the chemical problem in the correct context and choose the most suitable methodologies of investigation.

Exercises of thermodynamics concerning physical transformations and chemical reactions.
Phase diagrams of pure compounds.
Ideal and real mixtures.
Kinetic equation and reaction mechanism.