Dipartimento di Scienze della Vita e dell'Ambiente - Guida degli insegnamenti (Syllabus)
Knowledge of the topics of the courses on Mathematics, Physics, General and Organic Chemistry.
The course consists of theoretical lectures (5 credits, 40 hours) and laboratory practical work carried out individually or at small groups (1 credit, 16 hours) and fieldwork. An e-learning didactic activity is available in parallel to the normal frontal course. It includes: the didactic material, the self-evaluation tests, numerical exercises, instructions for the laboratory exercises, booking for the laboratory exercises, a section for the upload of laboratory reports from the students, information and booking for the field work, attendances to lectures and laboratory exercises, results of examinations.
The course enables students to acquire the fundamental knowledge of the theoretical and methodological basis of main techniques for chemical analysis (gravimetry, volumetry, potentiometry, conductimetry, UV-Vis spectrophotometry), and their applications in real matrices (spring waters, river waters, snow, atmospheric aerosol).
Ability to apply the knowledge:
At the end of the course, the student should also acquire the following professional skills: ability to carry out basic laboratory chemical analyses (gravimetric, volumetric, potentiometric, conductimetric, UV-Vis spectrophotometric) devoted to the analytical control of real matrices included the step of field sampling.
The execution of laboratory analyses (alone or in-group), as well as the drafting and editing of reports on the exercises carried out, contribute to improve for the student the degree of judgement autonomy in general, the communicative capacity (which derives also from the teamwork), the learning capacity in autonomy, and the ability to draw conclusions from experimental data.
Content (lectures, 5 CFU, 40 hours). Fundamentals of chemical analysis. Phases of the analytical process. Stoichiometric calculations of analytical chemistry. Quality of analytical data. Errors. Precision. Accuracy. Certified reference materials. Basic equipment for quantitative chemical analysis. Analytical balance and calibration control. Volumetric glassware and its calibration. Classical analytical methods of gravimetry and volumetry. Some instrumental analytical techniques: electrochemical (potentiometry, conductimetry) and spectrochemical (UV-Vis), with applicationsin the biological field.
Laboratory exercises (1 credit, 16 hours/student). Volumetric determination of HCl by strong acic-strong base titration and using acid/base indicators. Determination of acidity of rain or snow by potentiomentric titration. Conductimetric titration of HCl with NaOH. Determination of chlorides in river water by conductimetric precipitation titration. Determination of iodides, fluorides and chlorides in river water and hot spring water by direct potentiometry (calibration curve method). Spectrophotometric determination of nitrites in river water (calibration curve method). Spectrophotometric determination of Fe(III) in river water (standard addition method). At the end of the exercises, the student will have to consign (electronically) a report on the laboratory activity showing, for each experiment: the data obtained, the calculations performed, the analytical results computed (expressed with the correct number of significant figures), and their discussion and interpretation.
Field work (two one-day school trips). Two one-day school trips are expected to be carried out (one in winter, one in summer) dedicated to field activity: sampling of snow and spring water with analyses on site (pH, conductivity, chloride, fluoride, iodide, nitrate), and visit to plants for bottling of mineral water.
Methods for assessing learning outcomes:
The student consigns (on line) his own laboratory reports. The assessment method is a written classwork (open questions) and subsequent revision/discussion of the script. Thirty open questions are provided for the examination, which include also numerical exercises on stoichiometric calculations involved on gravimetric and volumetric analyses. To each question, a score included between zero and one is assigned. Passing of the written exam is bonded to the acquisition, on the stoichiometric calculations, of a score of at least half of the maximum obtainable. To the sum obtained other two points are added to obtain the final result of the written classwork. Moreover, for the final grade, up to two points maximum will be assigned with reference to the reports of laboratory exercises. The exam is passed when the final score is higher or equal to 18. During the course of lectures it is also foregone the possibility of participating to “in itinere” written classwork (1st and 2nd partial test). The result of a partial test may be mediated with the other provided the obtained score be at least 15, with the constraint referred above. In case of negative or unsatisfactory result in one of the two partial tests, it can be retrieved in the immediately following examination session.
Criteria for assessing learning outcomes:
In the written classwork, the student will have to demonstrate to have acquired a sound knowledge of basics and methods (theory and practice) of the chemical analytical methodologies of gravimetry, titrimetry, potentiometry, conductimetry, spectrophotometry (UV-Vis). In the laboratory reports, the student will have to demonstrate of having achieved the capacity to apply the acquired knowledge during the course to the execution of simple laboratory analyses and the capacity to write critically, in autonomy and/or in-group, a test report.
Criteria for measuring learning outcomes:
The final mark is attributed in thirtieths. Successful completion of the examination will lead to grades ranging from 18 to 30, and 30 with laud.
Criteria for conferring final mark:
The final mark is attributed by summing to the evaluation of the written classwork that of the laboratory report, the latter up to two points. The laud is attributed when the score obtained by the previous sum exceeds the value of 30 and contemporaneously the student demonstrates complete mastery of the matter.
D.A. Skoog, D.M. West, F.J. Holler, S.R. Crouch. Fondamenti di chimica analitica, 3rd edn., EdiSES, Napoli, 2015.
D.C. Harris. Chimica analitica quantitativa, Zanichelli, Bologna, 2005.