Unit PHYSICAL CHEMISTRY 2
- Course
- Chemistry
- Study-unit Code
- 55009212
- Curriculum
- In all curricula
- Teacher
- Fausto Elisei
- CFU
- 12
- Course Regulation
- Coorte 2017
- Offered
- 2019/20
- Type of study-unit
- Obbligatorio (Required)
- Type of learning activities
- Attività formativa integrata
PHYSICAL CHEMISTRY 2
| Code | 55044306 |
|---|---|
| CFU | 6 |
| Teacher | Fausto Elisei |
| Teachers |
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| Hours |
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| Learning activities | Caratterizzante |
| Area | Discipline chimiche inorganiche e chimico-fisiche |
| Academic discipline | CHIM/02 |
| Type of study-unit | Obbligatorio (Required) |
| Language of instruction | Italian |
| Contents | Rotational, vibrational and electronic spectroscopies. Statistical ensembles and distribution laws. Partition functions of perfect gases: traslational, rotational, vibrational, electronic and nuclear factors. Applications of Statistical Thermodynamics to perfect gases, equilibrium constants and rate constants. |
| Reference texts | P. W. Atkins and J. de Paula, Physical Chemistry, Oxford University Press |
| Educational objectives | This module involves the conduct of frontal lessons with the main objective of introducing the student to the study of molecular spectroscopy (MO, IR and UV-Vis) in order to determine molecular properties such as binding length, force constant and properties of electronic states. In the second part of the course, statistical thermodynamics will be used to predict the thermodynamic properties of a pure system, the equilibrium constant, and the rate constant of reactive processes. It is expected that at the end of the course students will acquire the basic knowledge of spectroscopy and statistical thermodynamics. In particular, the student will have to know: the approximation of Born-Oppenheimer, the model of the rigid rotator, the effect of centrifugal distortion, the model of the harmonic oscillator, the normal vibrational modes, the effect of anonymity, the Morse's potential, the principle of Franck-Condon, the main selection rules, a configuration and its statistical weight, the probability function, the model of Gibbs representative assembly, the canonical partition function, the Boltzmann distribution function, the quantum distribution functions of Bose-Einstein and Fermi-Dirac, the transitional state model. The main skills to apply the acquired knowledge will be: interpret a MO, IR and UV-Vis spectrum, determine molecular properties from MO, IR and UV-Vis spectra, calculate the thermodynamic properties of an ideal gas system, calculate the equilibrium constant in the gaseous phase, calculate the rate constant of a reactive process, perform simple numerical exercises on the topics discussed, apply their knowledge to subsequent courses of study. |
| Prerequisites | In order to be able to understand the topics covered in the course, students must have basic knowledge of General and Inorganic Chemistry, Classical Thermodynamics, Atomic Spectroscopy and Mathematical Analysis as regards the use of derivatives and integrals and the description of the series. |
| Teaching methods | Lectures with slide shows. Some lessons will be dedicated to revision and deepening of the issues addressed, some others to carry out numerical applications. |
| Other information | Attendance is not compulsory but strongly recommended. |
| Learning verification modality | They consist of a written test followed by an oral test. The written test will be used to ascertain the level of knowledge and understanding of the topics covered during the course and will last a maximum of four hours, during which the student must solve numerical exercises on the topics covered. It will be followed by an oral exam which will have access to students who pass the written exam with a score equal to or greater than 18/30. The date of the oral examination is agreed with the students on the day of the written test and made public on the notice board of the degree course. This test will serve to clarify problems emerged from the written test and to check the communication ability of the student to use an appropriate language and an autonomous organisation exposure of the topics treated at lesson. The outcome of the test, both written and oral, together with the evaluation of laboratory activities carried out in the course of Laboratory of Physical Chemistry 2 will form the final grade. |
| Extended program | SPECTROSCOPY. General introduction. Electromagnetic radiation. Electric dipoles. Electromagnetic spectrum. Quantization of rotational, vibrational and electronic energies. Quantum numbers. Transitions. Absorption, Stimulated emission. Spontaneous emission. Selection rules. Transition probability and transition moment. Boltzman distribution. Transition intensity. Spectrum. Spectrometers and their components. Lambert-Beer law. Line width. Doppler effect. Lifetime effect. Collisional effect. Rotational spectroscopy. Introduction. Inertial moments. Rotational energy levels. Rotational transitions. Rotational spectra. Vibrational spectroscopy. Introduction. Vibrational normal modes. Vibrational energy levels. Harmonic oscillator. Morse potential. Spectroscopic and thermodynamic dissociation energies. Vibrational transitions. Selection rules. Determination of dissociation energies. Vibrational spectra. Transitions and vibro-rotational spectra. UV-Vis spectroscopy. Introduction. Born-Oppenheimer approximation and Frank-Condon principle. Vibrational structure of absorption spectra. Electronic spectra of polyatomic molecules. Absorption spectra of biomolecules.Deactivation channels of electronic excited states. Steady-state and time-resolved techniques. STATISTICAL THERMODYNAMICS. Statistical distribution. Distribution function and probability function. Configurations. Weight. Principle of equal a priori probability. Dominant configuration. Stirling approximation. Thermodynamic properties. Gibbs's method of the representative ensemble. Ergodic hypothesis and equal a priori probability. Microcanonical ensemble: molecular distribution, entropy, internal energy, pressure, temperature and chemical potential. Canonical ensemble: Boltzman distribution, method of undetermined multipliers, molecular partition function, camonical partition function, internal energy, entropy, pressure, molar thermal capacity, thermodynamic quantities for the canonical ensemble. Grancanonical ensemble: grancanonical partition function, entropy, pressure, mole number, PV product. Boltzman, Fermi-Dirac and Bose-Einstein statistics. partition functions of distinguishable and indistinguishable particles. Monoatomic ideal gas: traslational partition function, electronic partition function and thermodynamic properties. Biatomic ideal gas: harmonic oscillator approximation, vibrational partition function, electronic partition function, thermodynamic functions. Polyatomic ideal gas: traslational, rotational (linear, non linear, spherical and symmetric molecules), vibrational and electronic partition functions, thermodynamic functions, hindered rotation. Applications: chemical equilibrium, rate constant and numerical exercises. |
PHYSICAL CHEMISTRY LABORATORY 2
| Code | 55044406 |
|---|---|
| CFU | 6 |
| Teacher | Anna Spalletti |
| Teachers |
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| Hours |
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| Learning activities | Caratterizzante |
| Area | Discipline chimiche inorganiche e chimico-fisiche |
| Academic discipline | CHIM/02 |
| Type of study-unit | Obbligatorio (Required) |
| Language of instruction | Italian |
| Contents | Chemical kinetics: reaction rate; rate laws and rate constants; collision and activated complex theories; complex reactions; experimental techniques. Photochemistry: production and decay of excited states; photoreaction quantum efficiency and mechanism; stationary and pulsed techniques. 8-10 laboratory experiences. |
| Reference texts | P. W. Atkins and J. de Paula, Chimica Fisica, Zanichelli (5th Italian ed.) |
| Educational objectives | The student will become familiar with the most important notions of chemical kinetics and photochemistry, ability to solve numerical problems of these subjects and knowledge of the most widely used experimental techniques (classical and more advanced). In particular, the following objectives will be pursued: - Knowledge of the basic concepts of kinetics of chemical reactions, methods for determining velocity law, kinetics of consecutive and parallel elementary reactions. - Critical ability in judging reactions under kinetic and thermodynamic control. - Knowledge of classical analysis methods for the study of moderate and slow reactions, flow and relaxation methods for fast reactions, laser flash photolysis for ultra-fast reactions. - Knowledge of some examples: i) kinetics of linear and branched chain reactions, ii) kinetics of enzymatic reactions, iii) photochemical reactions - Ability to solve numerical problems on the topics dealt with. - Ability to perform quantitative analysis to obtain parameters such as reaction rate, activation energy, quantum yield of a photoreception, etc. - Critical ability in presenting in reports the results obtained, also using error handling. |
| Prerequisites | In order to be able to understand the topics covered in the course, students must have basic knowledge of General and Inorganic Chemistry as regards the concepts of chemical bonding, chemical reaction, chemical equilibrium and Mathematical Analysis regarding the use of derivatives and integrals. The latter concepts will still be treated in some alignment lessons of the course of Physical Chemistry. |
| Teaching methods | They are provided for approximately 21 hours of lectures in which the teacher explains the content of the course and about 36 hours of laboratory (in the afternoons 8) in which students perform experiments. |
| Other information | The frequency of the lectures is strongly recommended, that the laboratory experience is required. |
| Learning verification modality | They consist of a written test followed by an oral test. The written test will be used to ascertain the level of knowledge and understanding of the topics covered during the course and will last a maximum of four hours, during which the student must solve numerical exercises on the topics covered. It will be followed by an oral exam which will have access to students who pass the written exam with a score equal to or greater than 18/30. The date of the oral examination is agreed with the students on the day of the written test and made public on the notice board of the degree course. This test will serve to clarify problems emerged from the written test and to check the communication ability of the student to use an appropriate language and an autonomous organisation exposure of the topics treated at lesson. The outcome of the test, both written and oral, together with the evaluation of laboratory activities carried out in the course will form the final grade. |
| Extended program | Chemical Kinetics The rate of chemical reactions. Rate laws. Reaction mechanisms. Steady state approximation. Dependence of reaction rate on temperature. Chain reactions. Experimental techniques. Collision and transition state theories. Theoretical prediction of rate constants. Monomolecular reactions. Reactions in solution. Reactions on solid surfaces. Homogeneous and heterogeneous catalysis. - Photochemistry Production and decay of electronic excited states. Radiative and non-radiative transitions, vibronic and spin-orbit coupling. Jablonski diagram. Photoreaction: measurement of quantum yield and mechanisms. Comparison of thermal and photochemical kinetics. Stern-Volmer equation for the emission quenching. Stationary and pulsed techniques. - Laboratory exercises. 8 -10 practical exercises are performed on the following subjects: a) Chemical kinetics: determination of the order, the rate constant and the activation energy of chemical reactions. Enzyme kinetics. b) UV-VIS spectrometry: spectrophotometric determination of equilibrium constants (indicators, charge transfer complexes); electronic spectra of organic dyes. c) Photochemistry: quantum yield of photochemical reactions, fluorescence quenchings. d) Applications of quantum calculation methods for determining chemical-physical quantities. |