LABORATORY OF ANALYTICAL CHEMISTRY INSTRUMENTAL - MOD.1

The objectives of this laboratory are:
- to introduce the students to the application of the instrumental analytical techniques studied in the theoretical classes;
- to guide the students to data treatment and critical evaluation of the experimental results
- to develop the students' ability to exploit the potentialities of the studied techniques.

1. Knowledge and understanding
A) Knowledge and understanding of the fundamental principles of spectroscopic and electrochemical analytical techniques, of the laws on which they are based and of the equations that express them.
B) Knowledge and understanding of the elements that make up the instruments with which the spectroscopic and electrochemical analytical techniques are carried out.
C) To know the main characteristics of the process of acquisition and processing of experimental data, in particular concerning spectroscopy and electrochemical instrumentation.

2. Ability to apply knowledge and understanding
A) Ability to use the laws and concepts learned for the choice of analytical instrumental techniques for the resolution of an analytical problem.
B) Ability to understand the instrumental aspects and their connection with the theoretical basis of an instrumental analytical method.
C) Ability to collect experimental data (alone and / or in groups) and to process results consistently in the final results, to be made explicit by writing a scientific report.
D) Ability to understand the instrumental aspects and their connection with the theoretical basis of an instrumental analytical method.

3. Ability to judge
A) Ability to express a judgment on the application of a specific technique in a specific context.
B) Ability to perform a critical evaluation of the experimental results by recognizing possible errors and then propose alternative methods.
C) Ability to evaluate the logical consistency of the functioning of the instruments.
D) Ability to recognize errors through a critical analysis of the applied method.

4. Communication skills
A) Communicating the knowledge learned and the result of their application using an appropriate language, both in oral and written.
B) To develop the ability to work in a team, interacting with the classmates in a respectful and constructive way, assuming responsibility for their role in the team and fully respecting all the safety and prevention regulations in force in the chemical laboratory.

To follow this laboratory course it is necessary to get the approval in the following courses: Mathematics, Inorganic and General Chemistry and lab, Analytical Chemistry and Lab, as well as the frequency to the classes of theory of Instrumental Analytical Chemistry.

Laboratory exercises:
1. Atomic spectroscopy experiments with microwave plasma atomic emission spectroscopy.
a) introduction to the use of atomic spectroscopy instruments, calibration of the instrument, construction of a calibration plot, wavelenght choice.
b) quantitative analysis for the determination of analytes of environmental or industrial interest in different matrices with the calibration plot method.

2. UV-vis molecular spectroscopy experiments:
a) qualitative analysis of the absorption spectra of colored substances in aqueous solution.
b) quantitative determination of the nitrous nitrogen contained in water samples by UV-Vis absorption spectrophotometry using the Griess reagent and the calibration plot method for quantification.

3. Electrochemical experiences:
a) potentiometry: preparation and analytical use of electrodes of first and second species (Ag/Ag+ and Ag /AgCl). Measurement of the cell potential and verification of its variation as a function of the concentration of Ag+ and Cl-.
b) Cyclic voltammetry: study of the voltammetric behavior of ferricyanide ion on glassy carbon electrodes (GC), verification of diffusive control process, application of cyclic voltammetry to quantitative determination of the concentration of ferricyanide in an unknown sample.

In all the topics developed and in the laboratory activities, emphasis will be given to the aspects of economic and environmental cost related to the application of the instrumental analytical techniques studied. The choice of analytical techniques and the development of new methods should take into account the issue of sustainability.

Baldo M.A., Moretto L.M., Daniele S. Laborat, Ugo P. Laboratory notes.

D.A. Skoog, F.J. Holler, S.R. Crouch,Chimica Analitica Strumentale, EdiSES, 2009.
Skoog D.A., West D.M., Holler F.J., Fondamenti di Chimica Analitica, EdiSES, Napoli, 1998
Cozzi R., Prearo P., Ruaro T., Analisi Chimica Strumentale, 2ª ed., Zanichelli, Bologna, 1997.
K.A Rubinson, J.F.Rubinson, Chimica Analitica Strumentale, Zanichelli, 2002.
D.C. Harris, Chimica Analitica Quantitativa, Zanichelli, 2005.

The assessment of learning related to the laboratory activities is carried out by evaluating the written reports on each of the experiments conducted in the laboratory. The final vote of the reports will be the arithmetic average of the reports of each individual experience. The scientific consistency will be evaluated in reporting the experimental objectives, the data obtained experimentally, the correct use of the units of measurement and the significant figures, the ability to process the data following the standard methods of quantification (for example the construction of calibration plots, using the method of the standard addition or the internal standard), the use of simple statistical methods to establish the significance of the analytical datum.
At the end of the series of experiences, an individual individual written test will be conducted, to establish the degree of understanding of the experimental operations performed in the laboratory.
For the evaluation of the part of the laboratory, the realization of at least 80% of the programmed activities is required. Appropriate additional laboratory sessions are planned to allow for possible recoveries.

Laboratory classes:
a short introduction is made for illustrating the aim of the experiment (objectives, theoretical bases and software eventually applied); then the experimental work is carried out in small groups, following the procedure proposed in the lecture notes.
At the end of each experiment, the students must elaborate a short report on the experiment done, including data treatment and a critical discussion of the results obtained.

The final evaluation of the laboratory course (modules 1 and 2) is composed by the average of the marks obtained in a written test (only one for the two modules) and the reports of all the exercises.
This evaluation is part of the final mark of the theoretical and experimental course.

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