Instrumental Analysis I: Chemistry 4241

Text: Principles of Instrumental Analysis by Skoog andHoller and Nieman, fifth edition

M. Bushey, Fall 2000

Lecture

Dates                                      Topic                                                               Chapter 

Aug. 29                  Intro.                                                               1, especially 1D, 1E           

Sep. 5                    Combating Noise                                                                          5

Sep. 12                  Noise cont./Experimental Optimization                                handout

Sep. 19                  Experimental Optimization cont.

Sep. 26                  Instruments for Spectroscopy                                 7, background: 6

Oct. 3                    Instrumentation cont.

Oct. 10                  Beer’s Law: Molecular UV/VIS                                               13                        

Oct. 17                  Molecular UV/VIS Applications                                              14

Oct. 24                  Molecular Fluorescence                                                              15

Oct. 31                  Atomic Absorption                                                                       9

Nov. 7                   Non-flame Atomic Techniques                                                 10

Nov. 14                 IR                                                                                        16, 17

Nov. 21                 NMR                                                                                         19

Nov. 28                 NMR cont.

Dec. 5                    open – x-ray? Surface techniques?/evaluations

Midterm, Tuesday Oct. 17 during lab time.

Dec 14, Thursday, 2:00 PM                        Final Exam

 

            This course explores how chemists use instruments to obtain chemical information. We will examine how these instruments work, how they are best used and what type of performance we can expect. This course focuses on experimental design and optical methods.

            This is a 2 credit course, with 1 hour for lecture for a total of 14 lectures and the remainder assigned to lab time. There are 5 experiments which are designed to be performed in course of 2 afternoons (provided you are properly prepared). You may find that even the longer labs can be completed in one afternoon provided you are properly prepared. It should not be necessary to repeat an experiment or to schedule additional time in order to complete the required work.

            Sometimes a lecture topic will not be explored in the lab and a lab topic will not be discussed in the lecture. You should expect this to be the case as it is through the combination of lecture and lab that you will gain in experience and understanding of instrumental analysis.

            Although attendance at course lectures is not explicitly required, I generally expect you to attend the lectures. I realize that situations may arise which cause you to miss an occasional lecture. I do not expect this to occur on a regular basis. If you miss a lecture, it is your responsibility to obtain class notes, or to make arrangements to complete any missed course requirement. Also, although I would prefer that everyone arrive at class on time, I prefer that you come to class late rather than not at all.                                                                                              


                                                                     Laboratory Schedule   

                                                                                                                                                           

Atomic Absorption/Emission, UV/VIS, Fluorescence, NMR, IR                                                                                                                                                                                                                                       

                                                                                                           

Date                      Team I                                       Team II             

Aug.29                   lab lecture---      

Sep. 5                    UV                                              off

Sep. 12                  UV report due 9/19                     IR                                                                      

Sep. 19                  off                                               IR, due 10/3

Sep. 26                  IR                                               UV                     

Oct. 3                    IR due 10/18                               UV, due 10/18

Oct. 10                  Fluor                                           NMR

Oct. 17                  no lab------- midterm Exam-------------

Oct. 24                  Fluor, due 11/14                         NMR, due 11/14                        

Nov. 7                   AA                                              Fluor                  

Nov. 14                 AA, due 11/28                            Fluor, due 11/28

Nov. 21                 NMR                                          AA                     

Nov. 28                 NMR, due 12/5                           AA, due 12/5

Dec. 5                    no lab------possible extra lecture time

 

 

Due Dates for Analytical Chemistry article summaries:

Issue Date            Due Date

9/1                         9/19                            

9/15                       10/3                             Six may be turned in for 10 points of extra credit each.

10/1                       10/24

10/15                     10/31

11/1                       11/19

11/15                     11/28

 

                                                                             Grading

                                          five experiments @ 100 pts each                                   500

                                                (30% yellow sheets, 70% group report)

                                          midterm exam for lecture section                                   100

                                          final exam for lecture section (cumulative)                      200

                                          final exam for lab section                                                 50           

                                          Analytical Chemistry summaries                                    (60)

                                                (optional, 10 pts. each)

                                                                                                                                   

                                          total                                                                    850 (910)

 


                                                                       Grading

Late reports will be penalized 5% per day late. Due dates for late reports with no penalty must be negotiated with the instructor prior to the original due date. All notebook information is due at the same time as the formal reports. Report formats are discussed below. Notebooks will also form a substantial portion of the lab grade. Notebook formats are also listed below. Notebooks and lab reports are due at 12:45 PM on the day indicated except for the last report of the semester which is due at 5 PM on the day indicated.

While not every analysis is perfect, the following are a few errors which can substantially lower laboratory grades: failure to properly specify the time and date of critical records; loss or corruption of electronic data or irreplaceable hard copy data; statistically bad results; poor graphical presentation of data; “blunders”; use of scrap paper in place of notebooks, inappropriate use of balances, weighing paper, glassware, etc., failure to clean up the work area or glassware at the conclusion of the experiment.

Analytical Chemistry extra credit article reports:  Analytical Chemistry is published on the 1st and 15th of each month. This is the journal for this field. You can make use of the library subscription or our online subscription. The journal is divided into two sections, “A” page articles and research articles. Questions based on specific “A” page articles may appear on the final exam. You may to turn in 6 summaries, each from a different issue date, 1 to 2 pages in length, for 15 points of extra credit each. Note: late article reports will not be accepted unless special circumstances have been discussed in advance. The articles you choose must be full length papers, not correspondence or technical notes. You should make efforts to choose articles from a wide range of topics. Each report you choose to turn in must be from a different journal issue. A full literature citation is required on all submitted article summaries. Do not submit of the article since I have my own subscription. In addition to the formal reports, you are encouraged to browse the journal, and at the very least, read several of the abstracts.

 

                                                                            Lab Organization

            This laboratory is designed around a team concept. You will be working in teams of three. Each of you will have a specific and assigned role to play for each of these experiments. The reasons for organizing the class this way are many. One of the more important reasons is that this type of organization mimics what is often found in industry. While it may be several years, if ever, before you enter chemical industry, working in a team setting forces you to work and interact with other people, a valuable skill. Although during much of your time here at Trinity you have worked individually on your chemistry, rarely do chemists work alone.

            The labs you will be performing this semester can be completed in one or two three hour afternoons, but only if you come to lab prepared and ready to begin work. If you come to lab not knowing how to manipulate the software of a particular piece of equipment, or without having mixed crucial solutions, or without knowing how to mix particular solutions, you will not finish these labs in time. It is vital for the success of these labs that you are prepared on Tuesday afternoon. By dividing the work for these labs into three components, the overall workload of this class is lessened. Some of you will be required to work on aspects of these labs prior to Tuesday, some will be required to work on aspects after Tuesday, each group member is required to be in lab on days your group is actually performing an experiment. You have access to all equipment for at least two weeks in order to complete the experiments.

            The three roles for each team are: Reporter (Manager), System Software and Operation, and Solution Preparation. The general duties of these roles are described below. Reporter/Manager. The Manager is in charge and responsible for the design, organization, and implementation of the experiment. The Manager is responsible for the outcome and reporting of the experiment and for inter- and intra-team communications and division of labor within the team. The Manager does pre-experiment library research and prepares the final report on an experiment, based upon the individual and intra-team reports. All other team members are answerable to the Manager. The Manager must submit an evaluation of the performance of each group member with each experimental report. The Manager may delegate authority within the team but cannot delegate responsibility.                            

            Solution Preparation. The person is responsible for the acquisition, preparation, blending, and delivery of all reagents, standards, and samples based upon the Manager’s instructions and the experimental needs. Most of this work must be done before the scheduled laboratory period if the team hopes to finish an experiment in a single afternoon.

             System Software and Operation. The person is responsible for the preparation and operation of the instrumentation. The person actually performs the analysis and whatever pre-experiment research is necessary to ensure safe and reliable instrumental operation. Much of this work, familiarization of the instrumental operation and software, must be done before the scheduled laboratory if the team hopes to finish an experiment in a single afternoon.

            Note that the work load of these positions will vary from experiment to experiment, and the managers should feel free to redistribute duties as deemed necessary. The only duty that cannot be redistributed is the writing of the final report. However, while the manager is the report writer, all team members are expected to be thoroughly familiar with the report contents and may be expected by their managers to contribute to data interpretation.

 

                                                                                   Reports

            As stated, the Manager prepares the final report. The grade on this report will be 70% of the teams’ grade on the experiment. The other 30% comes from the individual notebooks. There are a few other general rules. Although the System Operator actually performs the experiment, all team members must be present when the experiment is actually run in order to provide all components of information input into the experiment. Intra-team communication is extremely important. At the conclusion of the experiment, all team members should be thoroughly familiar with all aspects of the experiment. All team members are responsible for informing all other team members about their individual roles. It is also necessary for all team members to keep proper laboratory notebooks. A key factor in my grading the notebooks will be whether or not I think the entire experiment could be repeated from any of your notebooks. All notebooks should have two copies of any instrument output (one taped into white pages, one taped into yellow pages), all calculations and conclusions. Each team member should sign the report and keep a personal copy. A copy of raw data and final data work up is part of the report. The report is a stand-alone document, separate from any lab notebook. Although only the Reporter will be preparing the final report, each team member is expected to be knowledgeable about the report contents. Reports will not be returned. Questions based on the specific reports will appear on the lab final for up to 50 points of credit.

            In addition to the report itself, for each experiment, the Manager must submit an evaluation of each team members’ contribution to the final analysis. This evaluation must be initialed by the team member in question signifying that they have had the opportunity to read the evaluation. In addition, each team member, including the Manager, is assigned a contribution percentage, typically 100%. If a team member does not live up to the group expectations then their percentage should be reported as less than 100%. However, this means that someone took up the slack and someone else’s percentage should then be reported as more than 100%. The total for each group must be 100 x # of group members. This percentage will be multiplied by the assigned grade to determine individual grades.

            Should a team member prove to be repeatedly unreliable and repeatedly fail to live up to group expectations and norms, the Manager has the right to “fire” the group member. The remaining group members will then be expected to carry out the duties of this person. The dismissed group member must then negotiate with Upper Management for the opportunity to complete the course requirements. In order to avoid this situation, Managers and groups are encouraged to respond and rectify potential problems at their earliest appearance. 

            Reports and notebooks: As stated, the reporter/Manager prepares the report on each experiment for the entire group. Each report should begin with

>a title, experiment date(s), the Manager’s evaluations of each group member and the percentage contributions for each group member.  Each group member must sign this page.

 

>a brief statement of purpose

 

>a brief introduction section outlining the principles of the experiment. Do not make this section too long!

 

>an experimental section with provides details on solution preparation and experimental design sufficient in detail so as to allow duplication of the experiment by someone of similar experience. Any deviation from the handout should be clearly noted. Any blunder, etc. should be clearly noted. Mention should be made of which team member performed which duties. This section is ideally fashioned after the experimental section of Analytical Chemistry articles.

 

>data presentation, including any calculations, tables, graphs, or printouts comes next. Make sure all data items are properly labeled. Graphs should be presented in a manner suitable to support the conclusions with the appropriate labels and units. Raw data can be included in an appendix. Label all raw data, and present it in an easily readable form!

 

>data analysis and concluding comments, reference to literature data should follow. Include a bibliography section for literature references. A brief mention of any possible sources of error and how this affects results should be included. Be sure to answer any questions from experimental handouts.

 

The entire report, excluding figures, tables, and raw data, should not exceed six pages!

 

                                                                                 Notebooks

            Your laboratory notebook is the only medium through which you can legally communicate the experiments and their results that you have accomplished. Your ability to keep an accurate and complete record is the measure of your research capabilities. All members of the research team are required to maintain their research notebook up-to-date according to the general guidelines outlined in this instruction form.

            All work is dated with the date of the work evident on each page of the notebook, usually on the top of the page or in the left hand margin. A separate page should be reserved for each experiment that you perform, even when you are performing a series of experiments. each experiment should be given a brief title which may be as simple as “MEKC of Tea Components”  or “GC-MS of Fluorene”. The same title should be listed in the index. Reserve the first two pages of your notebook for the index. You are required to keep the index up-to-date. Upper Management reserves the right to spot check anyone’s work at any time. You are allowed to use one notebook for 4241 and 4243.

            The format for each experiment is as follows:

>After listing the title, a brief experimental purpose should be given. If appropriate, a chemical equation should be provided. Besides each major reactant, product, or compound of interest, list its physical characteristics and constants.

 

>A table of reagents should be provided, clearly listing the chemical name, structure, source, amount actually used (g, mL), number of moles actually used, an accurate description of the measuring device used.

 

>An exact description of the lab activities, in sufficient detail so as to allow another person to exactly follow your procedures. Observations, detailed methods, etc. should be included in this section. Think of this section, in particular, as a diary of your laboratory experience. -- Since you will be divided into teams in this course it is extremely important, that any team member’s notebook be sufficient to duplicate the experiment. You will need to be explicitly clear as to which information is simply obtained from another group member’s notebook and which information is original to your notebook. It is important that no data be missing from anyone’s notebook. Equipment settings, model numbers, etc. should be included.

 

>Analysis of the data follows as well as interpretation of the results including clearly outlined calculations. Everyone’s notebook should contain this section. No notebook will be considered complete without an analysis of the data. 

 

>Comments regarding suggestions for future changes in the lab are always welcome.

 

            Each notebook page should have the legible name and the signature of the notebook owner. No more than one line should be skipped in a notebook at any time unless a single line is drawn through the extra lines clearly indicating the intention to keep those lines blank. The notebook must be legible to another person. The notebook can be used for scratch work, etc. as long as these sections are clearly identified. Mistakes, etc. can only be indicated by a single line through the offending material - no erasures, white-outs, etc.

            Managers in particular may have additional information in their notebooks. This information may be important in planning the experiment or in commenting on the quality of other group members work and data. As always, think of the notebook as a diary of the total experiment.