SM/0116 - PHYSICAL CHEMISTRY 1 LABORATORY
Academic Year 2021/2022
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SILVIA PORCEDDA (Tit.)
- Teaching style
- Lingua Insegnamento
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Knowledge and understanding:
The student must know the principles that underlie the physical-chemical determinations investigated. In particular, the student will acquire knowledge of the main types of phase diagrams and quantities that highlight the deviation from the ideal behavior of real two-component systems. The student must be able to understand a physical-chemical question.
Ability to apply knowledge and understanding:
The students will have to master the physical-chemical formalism, to correctly perform the experimental determinations and to analyze the data concerning thermodynamic quantities and systems dealt with from a conceptual point of view in the lectures and/or experimentally investigated. They will also have to be able to read different phase diagrams of pure compounds and mixtures. The student must be able to set the resolution of numerical exercises of a physical-chemical type. In the laboratory, the students, working in groups, will have to learn how to organize and carrying out the experiments.
Autonomy of judgment:
The student must be able to identify the connections between theory and experimental determinations and make the most appropriate choices in the execution of experiments and in the writing of the reports containing the processing of experimental data.
The communication skills will be improved thanks to the work of writing the reports and the preparation necessary to be able to take the oral test.
The ability to learn will be developed during the individual study hours, in performing the preparatory calculations of the experiments, during the resolution of the exercises and in particular in the drafting of reports and in the data processing by means of calculation sheets and graphics programs.
Required knowledge: basics of arithmetic, algebra, analytical geometry, mathematical analysis, physics, general chemistry, stoichiometry and physical chemistry. It is essential to have reached 30 CFU, regularly registered, having passed examinations of: General and Inorganic Chemistry and Laboratory, Mathematics 1, Mathematics 2 (Institutions and Exercises of Mathematics I for students registered in 2016 and earlier) and having attended the course of Physical Chemistry I.
• Introduction to the course. IUPAC conventions in physical chemistry. 2 h.
• Recalls on the first principle. Description of the calorimetric bomb. Operating principle of the adiabatic calorimeter and evaluation of the involved ΔT. Determination of the ΔU and calculation of the related ΔH value. Experimental procedure for the determination of the combustion heat, at constant volume, of sucrose, cane sugar, salicylic acid, vanillin and others. 2 h.
• Phase diagrams of one and two-component systems. The phase rule, the rule of coordinates, the chord rule and the lever rule. Reading the different types of phase diagrams. 2 h.
• Overview on liquid-liquid equilibria. Description details of the determination of the isobaric phase diagram (T, w 100) related to the liquid-liquid equilibrium of the system: 1-propoxy-2-propanol + water. 1 h.
• The phase diagrams relating to liquid - solid equilibrium. Overview of some types of phase diagrams relating to binary mixtures in which the two constituents are totally soluble in the liquid phase and in the solid phase: i) totally soluble; ii) partially soluble; iii) totally insoluble. Temperature and eutectic composition. Description of the experimental procedure concerning the determination of the phase diagrams from the analysis of the cooling curves for the Bi + Sn system. 2 h.
• The phase diagrams relating to the liquid-vapor equilibrium. Vapor pressure and Raoult's law. Overview of deviations from Raoult's law: positive and negative, strong and weak. Azeotropic mixtures. Determination of the composition of a liquid from refractive index measurements. Experimental details concerning the construction of the diagrams (T, x, y) and (x, y) and identification of the azeotropic composition for the 1-propanol + water system. 2 h.
• Partial molar quantities. Definition of mixing quantities. Relationship between density and average molar volume, Vm. Application of the Vm intercept method for the determination of partial molar volumes. Calculation of excess volume, VE. Operating principle of the vibrating tube densimeter. Calibration. Experimental details concerning the determination, by means of densitometry, of the partial molar volumes, at 25.00 °C, of the components of the water + ethanol system. 2 h.
• Definition of dynamic and kinematic viscosity. Description of the experimental determination of the viscosity of mixtures 1,2,3-propantriol + ethanol at different temperatures. The Arrhenius’ law. Determination of the Arrhenius parameters for a pure compound. 2 h.
• Elements on electrolytic conduction. Method of determining the acidity constant of a weak acid starting from the conductivity values. Description of the experimental determination of the acidity constant of trichloroacetic acid in water. 1 h.
Preliminarily, the student will follow a series of classroom lectures (16 h) in which the experimental methods and procedures are illustrated.
In the laboratory, students will work in groups of 3 or 4 people. During the laboratory exercises (48 h), each student will carry out the experimental and calculation activities foreseen by the program. The last two lessons of the course will be dedicated to individual numerical exercises. During the exercises or during the individual study hours, each student will have to solve the numerical exercises that will be assigned during the course.
Teaching will be mainly delivered in person, possibly supplemented by online activities. In the event that it is necessary to change the delivery methods, the contents and activities of the course will remain unchanged.
The report file, one for each group, and the notebook with the exercises solved by each student, must be delivered at the end of the course and in any case at least 10 days before the exam date. Each student can also provide an additional document containing details, comments and personal remarks.
Verification of learning
In order to pass the exam it is necessary: to perform all the experimental determinations foreseen, to have carried out the group and individual numerical exercises, to present the relative reports containing the elaboration of the results and, finally, to pass an oral test. The proposed exercises will concern the application of the topics addressed during the course. • Calorimetry and thermochemistry. Concerning binary mixtures: • reading of state diagrams; • use of partial molar volumes and other volumetric properties; • applications of Raoult and Dalton laws; • viscosity and its dependence on temperature. The oral exam - in presence or online - can only be taken by students who are up to date with the preparatory requirements. The student will have to demonstrate to know - from a chemical-physical point of view - the quantities involved, the methods used in the experimental determinations and to be able to interpret the state diagrams studied.
The evaluation of the exam will take into account, for 50 %, the oral test, for 25 %, the evaluation of the reports and experimental skills demonstrated in the laboratory and for 25 % of the calculation skills demonstrated in the individual numerical exercises and exercises reported in the notebook.
Each paper and every answer, given in writing or in oral form, to a particular question is evaluated according to the following Docimological Table.
Rating Evaluation criterion
30 with honors. The answer is flawless from every point of view.
28 - 30 The answer to the question is direct, conceptually and formally correct, complete and articulated. Where appropriate, mathematical deductions are presented and described. The narrative buildup is particularly rich and precise and makes use of critical and personal ideas; the mastery of language and knowledge are appropriate in every single detail. The student is able to make links between different topics.
25 - 27 The answer to the question is formally correct but the most appropriate methods of resolution have not been adopted. The exposition is clear and fluid; the language property is adequate and the knowledge is good even if not particularly rich in details.
22 - 24 The answer to the question is affected by inaccuracies or distracting errors. The exposition is clear but affected by hesitations or repetitions; the property of language is limited but the knowledge is adequate even with some uncertainty.
18 - 21 The answer to the question, even if correctly set, is affected by significant errors and inaccuracies. The exposition is unclear; language ownership is limited and knowledge is barely sufficient. The student is not able to make connections between different topics.
1 – 17 The student commits serious conceptual errors or errors. The question is not understood.
0 The answer is not provided.
P. Atkins, J. de Paula Physical Chemistry, 5th edition, Zanichelli 2012.
Robert A. Alberty "Physical Chemistry" seventh edition, John Wiley & sons, New York, 1987 or following. Subject: Deviations from Raoult's law.
G. Morisi Chiorboli, " Riassunto delle lezioni del corso di Esercitazioni di Chimica Fisica ", Part I, Cap II. University of Bologna. Subject: Liquid solid equilibria phase diagrams.
IUPAC Green Book, Quantities, Units and Symbol in Physical Chemistry, RSC Publishing, 2007, Third Edition.
Operating manual for densitometer 4500 Mettler Toledo
Operating manual for viscometer SVM 3000 Anton Paar
Operating manual conductivity meter mod. 120. (ANALYTICAL production, Cinisello Balsamo MI),
Communications regarding enrollment in the course will be disclosed by publication on the website of the course of study and in that of the teacher:
Communications, course slides, texts of exercises, exercises carried out and various didactic material will be made known by posting on the chat or sharing files on the course team - PHYSICAL CHEMISTRY I AA 2122 LABORATORY - specially created on MS-TEAMS.