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Instrumental Analysis Laboratory Fall, 1999
Instructors:
Purpose: 1. To introduce experimental methods and instrumental techniques used in analytical, physical and inorganic chemistry. 2. To provide a physical understanding of the principles of analytical chemistry and to show how theses principles are applied in chemistry and related disciplines. 3. To instill the spirit of inquiry, initiative, independence and the ability to use the literature and help make the transition from performing assigned experiments in a highly structured laboratory (CH 103/104 and CH 241/242) to experimental chemical research. Text for Lecture: Harris, D. C. Quantitative Chemical Analysis, 5th ed., W. H. Freeman; New York, 1998. Resources and References:
1. Chemistry 311 binders (in the instructors' offices) Requirements: 1. Complete the following 4 experimental projects.
I. Calibration of Laboratory Glassware (Application of error and statistics) 2. Maintain a research style laboratory notebook. 3. Participate in lab projects enthusiastically and professionally, which includes keeping the laboratories clean and organized. 4. Write four reports in journal-style (Analytical Chemistry ) format. 5. Spend at least two laboratory periods per week working on your projects until your experimental work is complete. Meeting Times: The laboratory (BIH 459 ) will be open Monday-Thursday 1:30 - 4:30. No work will be allowed in the laboratory in the evenings, Fridays, or weekends without prior permission. Lectures will be on MWF at 11:15 AM - 12:05 PM in BIH 503. Schedule:
Grading Each project is worth 25 points of the total grade (100 points). For each project, 5 points for Laboratory Notebook, 5 points for participation (which includes attendance, lab skill, enthusiasm, understanding of the project, housekeeping, etc.) and 15 points for laboratory report. Before you start to write the report, you must obtain your notebook and participation grade from your instructor for the project. Letter grade will be reported according to the final points:
A+ : 100-98.0 A: 97.9-93.0 A-:92.9-90.0 Report Due Dates: 5:00 p.m. on Oct 1 (F) , Oct 21 (Th), Nov 12 (F), Dec 10 (F) Lab reports returned to students will contain two grades and substantial comments for revision.* Reports should be revised keeping in mind the instructor's comments, then resubmitted within one week to receive the higher grade. *There will be no opportunity for rewrite on the last report. Late report policy Late reports without prior apporoval* or dean's excuse will lose 10% per day. Academic Misconduct The following statement on plagiarism has been adopted by the faculty (1983): As an academic community devoted to the life of the mind, Middlebury College requires of every student complete intellectual honesty in the preparation of papers, laboratory reports, and other academic exercises. The habit of intellectual honesty is essential to both intellectual and moral growth. Effective evaluation of student work and helpful instruction can take place only in an environment where intellectual honesty is respected. Plagiarism is a violation of intellectual honesty. Plagiarism is passing off another person's work as one's own. It is taking and presenting as one's own the ideas, research, writings, creations, or inventions of another. It makes no difference whether the source is a student or a professional in some field. For example, in written work, whenever as much as a sentence or key phrase is taken from the work of another without specific citation of the source, the issue of plagiarism arises. Paraphrasing is the close restatement of another's idea using approximately the language of the original. Paraphrasing without acknowledgment of authorship is also plagiarism and is as serious a violation as an unacknowledged quotation. (1997/98 Middlebury College Handbook, pp. 38-39) Plagiarism includes the use of someone elseÕs data without appropriate citation. The fabrication of data, although not plagiarism, is an equally serious form of academic misconduct. In May 1997, the faculty decided to require the honor pledge on all written work. Please include and sign the statement "I have neither given nor received unauthorized aid on this exam/paper." What does this mean for your lab reports? You will be performing your experiment with a partner, hence you will be sharing data, so you must credit your partner in your report. Your calculations, analysis, and write-up must be your own work. You are free to compare your results with your partner after your calculations are completeÑthis is an excellent way to check your results and a common practice among scientists. You are also free to consult with faculty, staff, or students about any aspect of your experimental method or analysis. You may work in groups on the homework assignment, but you must turn in your own set of answers. You must work independently on the exams. Cases of academic misconduct will be referred to the appropriate review procedure. For more information, see the Middlebury College Handbook.
I. Calibration of Volumetric Glassware (Harris, Exp 27-1) (Larrabee) II. Atomic Absorption Spectroscopy (AA) (Larrabee)
1.Lead in Vegetation and Soils, CH311 binder III. High Performance Liquid Chromatography (HPLC) (Choi)
1. Analysis of an Asthma Medication, J. Chem. Ed., 1988, 65, 905. IV. UV/Vis Absorption Spectroscopy (UV/Vis) (Choi)
1. Artificial Food Dyes, CH311 binder. Instruments Each instrument has a logbook. You must sign up for instrument time to reserve a slot. Priority will be given based on the officially scheduled laboratory hours; otherwise, it will be on a first-come-first-served basis. You must fill in the logbook when you use an instrument. If an instrument breaks or does not appear to work, report the event and any symptoms in the logbook and to one of the instructors. For most of the equipment there are short written instructions posted near the instrument.
Your laboratory notebook is the ultimate reference concerning what took place in the laboratory as well as the essential communication link between you and other people. As the permanent record of your experiment, use a bound notebook to take into the laboratory. 1. Each page of your notebook should have a clear heading which includes your name, the subject of the experiment, the date and a page number. 2. For each experiment undertaken, make an entry for it in a table of contents at the beginning of your notebook, including the experiment title, page number and starting date. 3. Outline the experiment in advance.
- Title and date 4. From this point on, the procedure being followed should be described in all essential detail. In the laboratory, use the notebook to record observations, data , graphs and calculations. Record all data directly in your notebook with pen in chronological order. All entries into the notebook should be in ink. If a correction is necessary, cross through the mistake without making it illegible. Your notebook should be sufficiently clear and detailed so that someone else could repeat your experiment using only your notebook. All instrumental data such as chromatograms, spectra, graphs, tables and charts should be neatly taped or glued into the notebook.
The report should be no longer than 20 double spaced pages including figures, conform to the ACS style manual and contain the following sections: Title: Choose a concise but descriptive title. Abstract: State briefly the purpose, significance, the major results, and conclusions of the experiment. The title, author and abstract should be included on a separate page. Introduction: The purpose, background (literature), relevant theory and methodology of the experiment should be introduced. Experimental: Describe how the experiment was done with enough detail for someone else to exactly duplicate your results. If a reference to a text or journal articles is sufficient, so be it. However, indicate any modifications of a literature procedure. Be explicit as to source, grades, purification methods and amounts of any chemicals used. Model numbers and manufacturers of instruments should be included. Results: Present your experimental results in a precise format such as tables and figures. All numerical results in your report should have the correct number of significant figures, error limits and units. I f the calculations are involved and/or tricky, they may be described more fully in an appendix. Results from other sources must be referenced. Discussion and Conclusion: State your conclusions and the interpretation of the results in light of the experimental goals. If any of the results were unexpected, indicate and explain them. Error Analysis Appendix: This section is a must, though rarely included in published journal articles. Include arithmetic estimates of random measurement errors and propagate these through to your experimental results. Also include known and possible sources of systematic errors, quantitatively discuss how these would affect your results and give suggestions, if you have any, for eliminating them in the future. References: These should be numbered consecutively and included at the end of your paper. Proper form for referencing is given in the ACS Style Guide or in the notes to authors found i n the January issue of ACS journals. Experiment Schedule Each pair of students will belong to a group classified by project.
1A Esi Asiedu and Eric Meissner Each day priority will be given to the group assigned to that instrument.
Week 12/1 Check Out whenever experiments are complete.
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