Publication in the Diário da República: Despacho nº 7835/2019 de 05/09/2019
5 ECTS; 2º Ano, 1º Semestre, 30,0 PL + 15,0 TP , Cód. 608012.
Lecturer
- Catarina Margarida Duarte Belo Calado Brito (1)(2)
(1) Lead Professor
(2) Teaching Professor
Prerequisites
Not applicable
Objectives
By the end of this course, students should be able to:
Understand the principles of the interaction between electromagnetic radiation and matter, on which spectroscopic methods of analysis are based.
Apply Lambert-Beer's Law and recognize its limitations.
Identify the main components of UV-Vis spectrophotometry, flame emission photometry, atomic absorption, and infrared equipment, and the function of each.
Distinguish the various spectroscopic techniques according to their operating principle, applications, and limitations.
Recognize the main types of interferences and ways to minimize them.
Apply the most common quantification methods: calibration curve, standard addition, and internal standard.
Understand the concepts of precision, accuracy, sensitivity, and detection limit.
Interpret simple spectra in qualitative analysis, including the identification of functional groups by IR.
Program
1. Visible and ultraviolet spectrophotometry. Radiation absorption. Lambert-Beer's Law. Chemical deviations from Beer's Law.
Nomenclature in spectrophotometry. Order of magnitude of concentrations and other quantities. Graphical presentation of data. Types of spectrophotometers. Components of spectrophotometers and their functions. Instrumental deviations from Beer's Law. Applications of ultraviolet and visible spectrophotometry. Qualitative analysis. Spectrum identification. Quantitative analysis: calibration curve and absolute method. Standard addition methods. Photometric titrations.
2. Flame emission photometry. Theoretical principles: Emission spectrum; Dissociation mechanism; Intensity of atomic spectral stripes. Instrumental systems: components of a flame emission photometer and their functions. Different types of flame emission photometry. Direct flame photometry and indirect flame photometry. Types of interference: Spectral, background emission, self-absorption, chemical ionization, and matrix effect. Flame photometry in analytical chemistry: precision, accuracy, detection limit, and sensitivity in flame emission photometry. Calculation methods: Calibration curve and internal standard addition method.
3. Atomic absorption spectroscopy. Theoretical fundamentals: absorption and atomization mechanism, atomic population, and Lambert-Beer law. Equipment: sources for atomic absorption; flame types; atomization systems and burners. Accuracy, precision, sensitivity, and detection limit in atomic absorption. Interferences. Qualitative analysis. Quantitative analysis: calculation methods - calibration curve and internal standard addition.
4. IR spectrometry. Theoretical fundamentals. Equipment.
IR spectra: band nomenclature; imprint region and typical absorption zones. Spectrum identification.
Practical Laboratory Work
1. Spectrophotometric determination of the pKa of bromocresol green indicator.
2. Turbidimetric determination of sulfate content in water.
3. Determination of potassium in water by Flame Emission Photometry.
Evaluation Methodology
The practical component (P) depends on the experimental execution of all practical assignments and the submission of the respective reports, which are evaluated and account for 30% of the final grade.
The group work (TG) consists of a research paper on a topic related to the content taught and accounts for 20% of the final grade.
The theoretical component (T) is evaluated through two written tests, each accounting for 50% of the grade for this component.
The final grade (CF) is calculated using:
CF = 0.3 P + 0.2 TG + 0.5 T
To pass, students must obtain a minimum grade of 10 in each component (P, TG, and T).
Exam Assessment
In the exam assessment, at any time, the theoretical component (T) is evaluated through a written test covering all chapters. The grades for the practical component (P) and the group work (TG) are maintained, and the CF is calculated using the same formula.
Passing the course requires attendance in at least 70% of the theoretical-practical and laboratory practical classes.
Bibliography
- Gonçalves, M. (2001). Métodos Instrumentais para Análise de Soluções. Análise Quantitativa.. Lisboa: Fundação Caloute Gulbenkian
- Grouch, S. e Holler, F. e Skoog, A. (2006). Principles of Instrumentation Analysis. New York: Brooks/Cole
- Rouessac, A. e Rouessac, F. (2007). Chemical Analysis: Modern Instrumentation Methods and Techniques. New York: Wiley
Teaching Method
Theoretical and practical classes with presentation of content and problem-solving exercises. Practical laboratory classes with the execution of experimental work and preparation of reports. Research work on the topics covered.
Software used in class
Not applicable
