Laboratory Techniques
Code
10824
Academic unit
Faculdade de Ciências e Tecnologia
Department
Departamento de Química
Credits
3.0
Teacher in charge
Ana Maria Ferreira da Costa Lourenço
Weekly hours
3
Total hours
31
Teaching language
Português
Objectives
Preparing students for the efficient conduct of the main experimental techniques used in chemistry: preparation of solutions, titration, determination of physical constants, recrystallization, sublimation, distillation, liquid-liquid extraction, solid-liquid extraction, filtration and chromatography.
Acquisition of experimental skills to perform the operations effectively, and safely as well as the acquisition of the knowledge necessary for a correct interpretation of results. It is intended that students acquire the fundamentals of general organization of the chemistry lab, safety rules, good laboratory practices, organized and accurate record of work done in the lab notebook and prepare reports.
Subject matter
Organization of a chemical laboratory. Safety and good laboratory practices. Environmental protection and waste management in the laboratory. Methodology of work in the laboratory: preparation work, experimental implementation, specification of laboratory preparation and submission of reports.
General laboratory techniques: measuring, mixing, dissolving, heating / cooling, stirring. Mounts for laboratory work. Preparation of solutions. Dilutions. Titration. Measurement of physical constants. Procedures for purification of solids, recrystallization and sublimation. Process for purifying liquids, distillation. Extraction processes: liq - liq and sol - liq. Filtration. Chromatography: column chromatography and thin layer chromatography. Analytical and preparative chromatography. Determination of contents in solution.
Practical sessions
1st session: Presentation of the Laboratory. Identification of general laboratory equipment. Safety rules in the chemistry lab. Weighing, preparing solutions, measuring volume and solutions preparation.
2nd session: Determination of physical constants: melting point, refractive index and density
3rd session: Preparation of acid and base solutions at different concentrations. Acid-base titration.
4th session: Purification of solids: recrystallization and sublimation.
5th session: Purification of liquids: fractional distillation. Demontration of distillation under reduced pressure and steam distillation.
6th session: Liquid-liquid extraction. Drying agents. Gravity filtration. Evaporation to dryness. Solid-liquid extraction. Notion of extract.
7th session: Column chromatography and thin layer chromatography.
8th session: Content determination. Preparation of solutions / dilution calculations / calibration line.
Bibliography
Introduction to Organic Laboratory Techniques, A Small Scale Approach. R.G. Engel, G.S. Kriz, G.M. Lampman and D.L. Pavia, 3rd ed. Brooks/Cole 2011.
e-escola IST (2006) http://www.e-escola.pt/ftema.asp?id=15&canal=quimica
CU Boulder Organic Chemistry Undergraduate Courses http://orgchem.colorado.edu/hndbksupport/ochemlabtech.html
Online Safety Library: Laboratory and Chemical Safety http://ehs.okstate.edu/
ChemKeys http://www.chemkeys.com/bra/index.htm
Teaching method
The course is on practical work in chemistry lab, supported the concepts that allow the acquisition of knowledge for the good performance of the experimental techniques and interpretation of results.
In the theoretical-practical classes are exposed to the fundamental theoretical concepts associated with the implementation of practical work with the help of Power Point presentations. Exercises are solved by the students on calculations associated with experimental techniques to implement in practical classes.
In each of the practical classes is made the exposure of specific concepts of work involved in writing direct the board, then the experimental work done by students in the laboratory.
Evaluation method
The UC has Continuous Assessment with the following:
Evaluation Components and Evaluation Elements (weighted)
i) Theoretical-practical Evaluation
a) individual mini-test (10%)
b) individual practical test to be held the last week of classes (30%)
ii) Laboratory Evaluation
a) student preparation of the practical works and performance in the laboratory practical classes throughout the semester (30%)
b) individual laboratory notebook (20%)
c) group report (10%)
1. The performance of all the Evaluation Elements is required, except the evaluation mentioned in 6.
2. Elements Evaluation i) a), ii) a), b) e c) are required to obtain Frequency.
3. The weighted classification of the Evaluation Components that give Frequency must be ≥ 9.5 values for UC approval.
4. The Evaluation Element i) b) must be ≥ 9.5 values.
5. Any other Evaluation Element does not have a minimum grade rating.
6. The performance of seven of the eight practical works corresponding to Evaluation Elements ii) a) is mandatory.
7. Lack of a second experimental work must be duly justified.
8. To perform the experimental work late students must register with their own teacher for the lesson recap created for this purpose at the end of the semester.
9. Failure to perform or fail in Component Assessment i) b) requires the written examination of Recurso in with 30% weighting for final classification.
10. For students who obtain Frequency but not approve the Evaluation Component i) b) can maintain the classification of Frequency for the following year.
11. Students with special status or workers can do experimental work in the a module condensate to be established for each case. These students are evaluated in the same manner as described above.