OVERVIEW

Analytical chemistry is an information science in the chemical field that deals with characterising the nature of chemical systems and identifying/quantifying their components of interest. “Analytical” derives, in fact, from the Greek verb analyo (ἀναλύω), which means to dissolve/break down. This discipline is aimed at solving complex problems by dividing them into their simplest constituents. From an application perspective, chemical analysis becomes a tool for controlling and guaranteeing reliability of processes and products.

AIMS AND CONTENT

LEARNING OUTCOMES

Providing the basic knowledge related to the blocks of any analytical process: formulation of the problem, choice of the analytical method, measurements, processing of chemical information.

AIMS AND LEARNING OUTCOMES

At the end of the course, the student will be able to:

• Order and describe the steps of the chemical-analytical process.
• Define the parameters for evaluating the quality of a method and of the analytical results, knowing how to use them in the context of a chemical-analytical laboratory.
• Describe chemical equilibria in solution, knowing how to approach the phenomenon and the key steps for its study.
• Interpret and illustrate the graphical representation of chemical equilibria in solution in an exhaustive way.
• Define the concepts of location, dispersion and the descriptive parameters for a probability distribution.
• Illustrate the different types of standardised distributions, being able to represent them graphically and to derive a proper interpretation.
• Understand the principles of statistical inference, describe and implement its use in statistical tests, set in the context of a chemical-analytical laboratory.
• Know how to present the key concepts of analysis of variance (ANOVA), univariate regression and bivariate statistical tests.
• Define the concepts of noise and drift in instrumental signal and describe the main methodologies for their minimisation.
• Know how to describe the Fourier transform and its use in signal analysis in a descriptive way.

TEACHING METHODS

The course is organised with 75% of frontal lessons: professors, with the help of multimedia presentations (including graphic material and videos), will illustrate the contents of the course. In addition, for the parts of chemical equilibria in solution and application of statistics, numerical exercises will be carried out and also assigned as homework. The last two lessons of the course will be dedicated to correcting the assigned exercises, as well as to conducting exam simulations for improving the self-assessment.

The remaining 25% of the course will be carried out in accordance with the most innovative participatory teaching strategies, in order to stimulate student learning. In particular, the following ones are envisaged:

• the use of an educational App, internally developed and downloadable from the AulaWeb platform. Through interactive graphics, the student will be able to test the knowledge acquired during the frontal lessons. This activity will allow the student to develop practical skills, improving the metacognitive control, intended as the awareness of the learning processes.
• a practical laboratory experience organised according to the principles of the flipped classroom and team-based learning: the student will receive literature to study before entering the laboratory, in which he/she will be faced with a problem to be solved. Group work and peer discussion will be stimulated by the professors in order to complete the required activity. Only afterwards, professors will present the theoretical contents describing, with an inverted lesson, what students have learned in the laboratory.

Depending on the health situation and on the University provisions, the teaching activity might be carried out remotely, with the support of MS-Teams. The course program and teaching methods will not be subject to changes, except for the practical laboratory experience.

SYLLABUS/CONTENT

Methodology of analytical chemistry (1 CFU)

Steps of the chemical-analytical process. Importance of sampling. Parameters for evaluating the quality of a method and of the analytical results: accuracy, precision, trueness, sensitivity, limit of detection and limit of quantification. Repeatability, intermediate precision and reproducibility. Use of primary and secondary standards. Accreditation. Traceability and trackability.

Chemical equilibria in solution (3 CFU)

Elements of kinetics and chemical thermodynamics. Activity and equilibrium constants. Algebraic and graphical study of the main chemical equilibria in solution. Speciation and calculation of equilibrium concentrations. Distribution fractions. Brønsted-Lowry acid-base equilibria. Buffering power. Lewis acid-base equilibria. Complexation reactions with unidentate and chelating ligands. precipitation/dissolution equilibria. Case of concomitant reactions. Redox equilibria. Flood’s diagrams. Semilogarithmic and logarithmic distribution diagrams. S and V neutralisation and titration curves. Pourbaix’s diagrams (potential vs. pH).

Applications of statistics in analytical chemistry (3 CFU)

Bases of descriptive statistics. Random experiments, population and sample. Absolute and relative frequency. Statistical regularity. Frequency and probability distributions. Central limit theorem. Normal distribution and cumulative distribution. Lilliefors’ normality test. Location and dispersion: descriptive parameters of a probability distribution. Standard normal distribution z. Confidence probability and significance. Significance intervals. Propagation of variances. Distributions of the mean, chi-square, Student's t, Fisher's F. Statistical inference and main significance tests based on the z, t, chi-square, and F distributions. Analysis of variance (ANOVA). Q and G tests for the detection of outliers. Bivariate confidence intervals and associated tests. Univariate regression with the least squares method. Calibration lines. Comparison between two analytical methods and Passing-Bablok regression.

Instrumental analytical signals and basic treatments (1 CFU)

Instrumental signals in the time domain and in the frequency domain. Drift and noise. Fourier transform (outline) and associated filters. Moving-average filter and Savitzky-Golay polynomial filter.

RECOMMENDED READING/BIBLIOGRAPHY

Material provided by professors, in the form of multimedia presentations, contains all the information necessary for the study of the subject as well as for passing the exam. The material, updated annually, can be downloaded in .pdf format from the course website for the academic year of reference, on the AulaWeb platform.

Furthermore, two texts useful to deepen what is presented by the professors are indicated below:

• Chemical equilibria in solution: Valerio Di Marco, Paolo Pastore, G. Giorgio Bombi, "Chimica Analitica - Trattazione algebrica e grafica degli equilibri chimici in soluzione acquosa", EdiSES, ISBN 9788879598842.
• Appilcations of statistics in analytical chemistry: Michele Forina, "Fondamenta per la Chimica Analitica", Edizioni SISNIR, ISBN 9788890406461, freely downloadable from the site of the Italian Society of NIR Spectroscopy (http://www.sisnir.org/sisnir/download/fondamenta -for-analytical-chemistry) and made available through the AulaWeb platform.

Further bibliography:

• M. Forina, "Introduzione alla Chimica Analitica", ECIG, Genova, 2003, ISBN: 887545986X.
• D.A. Skoog, D.M. West, F.J. Holler, S.R. Crouch "Fondamenti di Chimica Analitica", EDISES, Napoli, 2005, ISBN: 8879593005.
• D.S. Hage, J.D. Carr, "Chimica Analitica e Analisi quantitativa", Piccin, Padova, 2012, ISBN: 9788829921188

TEACHERS AND EXAM BOARD

Exam Board

PAOLO OLIVERI (President)

CRISTINA MALEGORI

RAFFAELLA BOGGIA (Substitute)

MONICA CASALE (Substitute)

RICCARDO LEARDI (Substitute)

LESSONS

LESSONS START

Classes will start in accordance with the academic calendar. Any changes to the timetable will be communicated on the course wall on the AulaWeb platform.

Class schedule

The timetable for this course is available here: Portale EasyAcademy

EXAMS

EXAM DESCRIPTION

The exam consists of both a written test and an oral test.

The written test provides access to the oral test, but it does not include any associated rating and is considered passed only in the absence of errors. This test, to be carried out individually, consists in  6 numerical exercises (5 related to equilibria in solution and 1 related to applications of statistics) and has a duration of 120 minutes. The tests are generated using a dedicated software, in order to produce diversified exercises, but of comparable complexity, for each of the students enrolled in the exam. During the test, using a non-programmable scientific calculator, texts, forms and notes in paper format is permitted. The use of devices with internet access (even if disabled by the student) is not permitted.

To be admitted to the written exam, it is mandatory to register through the student portal.

The result of the written exam will be communicated by the professors by e-mail, individually, in accordance with the rules and directives for privacy protection. Passing the written test allows the student to be admitted to the oral test for which no further registration is required, and which will be carried out during the same session, no later than 10 days after the date of the written test. Date and time of the oral test will be communicated by the professors by e-mail, together with the notification of the result of the written test.

The oral test takes place in the presence of two examiners and focuses on the entire course program. The exam lasts an average of 45 minutes and includes a minimum of three questions: the first one focuses on equilibria in solution, the second one on the applications of statistics, and the third one either on the methodology of analytical chemistry or on instrumental analytical signals. A student can take the oral exam as the only candidate; in this case, in addition to the commission, the presence of a witness (usually chosen and contacted by the candidate) is required.

Depending on the current situation and on the University regulations, both of the tests might be carried out remotely, without any change in the modalities, through the MS-Teams online platform, in a dedicated channel that will be communicated to candidates in the days immediately preceding the written test. To allow teachers to supervise the performance of the tests, the candidate must keep microphone and webcam active for the entire duration of the exam.

ASSESSMENT METHODS

The written test will allow the teachers to verify the knowledge acquired by the student from a procedural point of view, by applying the basic concepts presented during the course in numerical exercises, of content and complexity comparable to those carried out in the classes. Only the correctness of the final result presented for each exercise will be considered, also in terms of how the result is presented (e.g., units of measurement). An exercise that, while respecting a correct procedure, presents an incorrect result (even if due to careless mistakes) will not be evaluated as correct.

The oral test will evaluate theoretical knowledge in greater depth and the creation of intra and interdisciplinary connections will be encouraged. In this way, it will be possible to verify in detail the achievement of the training objectives and the ability to correctly use the technical-scientific terminology of the sector. It will be required to place the theoretical concepts in the operational context of an analytical chemical laboratory, providing simple but concrete examples. During the test, ability to organise an organic speech and property of language will be considered as fundamental for achieving a full rating.

The combination of these two tests allows the teachers to verify, in a global way, the student's abilities in remembering and putting into practice the basic methods of analytical chemistry, widely used in most professional contexts.

Exam schedule

FURTHER INFORMATION

For any updates that may be necessary during the academic year, also due to changes in the health situation, students are referred to the course wall on the AulaWeb platform.

For students with SLD, disabilities or certifications of other special educational needs, it is requested to contact the teachers at the beginning of the course, to agree on teaching and exam methods which, in compliance with the teaching objectives, will take into account the different learning opportunities and provide suitable compensatory tools.