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Chem 219 Lab Report Guide (Title)
Chem S. Tree (Your name)
Lab Partner: Lab partner’s name TA: Kevin Fischer Date lab performed: 1 / 30 /201 8 Date report submitted: 2 / 6 /201 8 The first page is the title page – complete with a title, your name, partner’s name(s), etc. No page number for title page. Subsequent pages are numbered. Format: Font: Arial, Times New Roman, Calibri; size 11 or 12 Margins are 1” all around Text is double spaced Paragraphs (except for ABSTRACT) have a “tab” indent. Be sure to have a header inserted (see next page for header format). A few general points: Use a formal writing style and say what you mean succinctly o Do not use colloquial language or slang Avoid contractions For this class and these reports, address your writing to your peers: junior/senior chemistry students
Lab: Chem 219 Lab Report Guide date: 2/26/ ABSTRACT The ABSTRACT functions as a mini-paper. It succinctly summarizes what was said in the report. The ABSTRACT should have several brief parts (1-3 sentences each) in the following order: (a) statement of purpose, (b) experimental approach, (c) experimental elements that are key to the experiment, (d) major results, (e) comment on what the results mean or major problems arising that complicate interpretation, and (f) conclusion. Give the key results and data that are necessary to support your conclusions. Give real values—do not say “we measured some stuff” and got this conclusion.
You do not need to start each section on a new page.
INTRODUCTION
The INTRODUCTION (a) introduces the problem to be addressed and (b) tells why the work being done is important. The INTRODUCTION then goes on to tell (c) something about the experimental approach used in the experiment and why. The minimum length of the INTRODUCTION would therefore be 3 paragraphs. Think of the introduction to be an overture to the work. When you cite the work of others, cite it using parentheses as shown here. For example, I have published work looking at how leucine is metabolized in the body (1) and how amino acids are absorbed by the gut and liver (2-4).
Lab: Chem 219 Lab Report Guide date: 2/26/ Instrumentation. If specific piece(s) of instrumentation are central to the experiment and were used in specific modes, give the name, model, manufacturer and key features of the instrument. Procedures. Here is where you outline your experiment(s). Give an overview paragraph of the experiment(s) first; then give individual paragraphs concerning each experiment or sub- part. State clearly and succinctly what you did. The predominant approach to defining procedures has been to use “passive voice”. A simple example is: Samples were collected in 10-ml tubes, and the solvent evaporated under a stream of dry N 2 gas. When the tubes were dry, the derivatizing reagent was added. The tubes were capped and heated for 30 min at 100° C in an aluminum heating block. Data Analysis. You succinctly state the calculations you performed in this section. This section should describe how all results were calculated from data that you collected in your experiments. The RESULTS and DISCUSSION sections should not need to state or restate your calculations—they should be defined here. You give the key equations you used to calculate your data. You define all variables in the equation (generally after stating the equation), and you give units of measure for all variables. Simple equations can be written using normal word- processing. Really simple equations can be worked into the text. An example is: Blood glucose concentration ([G] , mM) was the product of the measured glucose per sample ( nG , nmol) and sampled aliquot ( V , μl): [G] = nG/V. When an equation is longer, it is set off in its own paragraph. All equations that are set off on their own line should have an equation number in parentheses at the right. An example is:
Lab: Chem 219 Lab Report Guide date: 2/26/ Homocysteine was determined from the ion intensity ratio of unlabeled homocysteine to [^2 H 4 ]homocysteine ( R0/4 ): n 0 = n 4 • [ R0/4 - R0/4(4) ]/ k0/4 , (Eq. 1) where n 0 is the amount of homocysteine (nmol), n 4 is the amount of [^2 H 4 ]homocysteine added to the sample (2 x the amount of [^2 H 8 ]homocystine), R0/4 is the measured A 411 /A 415 ion intensity ratio, and R0/4(4) is the A 411 /A 415 ion intensity ratio when pure [^2 H 4 ]homocysteine is injected. NOTE about chemical reactions: If they are really big, they go as figures (see Fig. 2). If they are a single reaction or compound, they are inserted like an equation and numbered as a “scheme” (Scheme 1) Statistics. The final component of data analysis is “statistics”. How did you prove that a given result was significant? Here is where you state what kind of statistical tests you applied to the data: unpaired or paired t-tests, analysis of variance, linear regression analysis, etc. The length of the EXPERIMENTAL section will probably be ~2-4 pages (assuming no background theory is required). Reminder: “data” is plural, “datum” is singular. So not: “the data show s …” but “the data show.”
Lab: Chem 219 Lab Report Guide date: 2/26/ may have used the optimal settings obtained in the first part to take experimental data. If so, start out by telling the reader that “before you could investigate the spectroscopic properties of the compound dimugleoglugtane, you first needed to optimize the conditions of the spectrometer. To do that you first measured trimethylsimplene as the model compound to test various spectrometer parameters.” Then you can present your data for this part: “Fig. 1 shows the spectrum of trimethylsimplene obtained where __ resolution was used. Note that the individual peaks overlap. However, when resolution was increased to __, the individual peaks became resolved (Fig. 2).” …and so one to tell the story of your RESULTS of your experiments in a logical fashion. DISCUSSION This section is where you discuss your results. That is, you say what is important about them--good and bad. You put your results in context with information already in the literature. Often times, the first paragraph of the discussion is a restatement of the problem and why you are doing what you are doing. That paragraph makes it easier to slide into giving the strength and weaknesses of your findings and comparing your results with the literature. Although it is not mandatory, most people have a final paragraph in their discussion that serves as a conclusions paragraph. The conclusions paragraph serves to summarize the important findings of the work. The length of the DISCUSSION section is dependent upon what you have to say. 2-5 pages should suffice.
Lab: Chem 219 Lab Report Guide date: 2/26/ LITERATURE CITED References will be cited in the text using numbers in parentheses (1) and then listed here numerically by citation order. You can use either standard ACS format or J. Biol. Chem. format for the citations. The references you see below are J. Biol. Chem. format. Do not quote anything from the literature without putting quotes around what you are “quoting.”
- Matthews, D. E., Bier, D. M., Rennie, M. J., Edwards, R. H. T., Halliday, D., Millward, D. J., and Clugston, G. A. (1981) Science 214, 1129 - 1131
- Matthews, D. E., Marano, M. A., and Campbell, R. G. (1993) Am. J. Physiol. Endocrinol. Metab. 264, E109-E
- Matthews, D. E., Marano, M. A., and Campbell, R. G. (1993) Am. J. Physiol. Endocrinol. Metab. 264, E848-E
Lab: Chem 219 Lab Report Guide date: 2/26/ Notes about producing figures (examples shown below): Figure 1. Provide a title sentence for the figure. Then give any supporting sentences you need to explain the figure and tell what is what on the figure. For example, what are the symbols? This section can be typed single space to save room. Notes: Be sure to annotate your figure axes clearly Be sure to use large enough type in your figures to be readable If you “scan” a figure, be sure that it is saved compactly as a JPEG, TIF, or GIF format and that it is clearly readable Other notes: Microsoft Excel:
- When you prepare a graph, you almost always want to choose the “XY Scatter” plot. Do not choose “Line” because “Line” gives you even spacing of the x-symbols, regardless of their value.
- Make sure the plot area is clear/white
- Do not use grid lines. Turn them off
- Do not use a title on your Excel figure. You add the title in Word as your figure caption text
- Format your x & y axes appropriately: a. Set the font to be appropriate (i.e. bigger than default) for your axis annotations b. Set the scale to be appropriate repeat patterns (e.g. “0, 5, 10, 15, 20…”, not “-0.5, 5.5, 11.5…” c. Use an appropriate number of zeros in your axes. Don’t have values of “0.000, 2.000, 4.000, 8.000” when “0, 2, 4, 8” are more readable and simpler d. Add an x-axis and a y-axis title that describes what the axes are. Be sure the title font size is as large or larger than you annotated numbers e. If you need to plot two traces of (i) significantly different scales (e.g. on has a maximum intensity of 1000 and the other has a maximum of 50) or (ii) different units (e.g. one is absorption and one is emission), then have one trace use the right Y-axis. (Right click on the series data and select “Format data series” and select “Secondary axis” under “Series options”.) f. If the scale of your axis is really big (e.g. 100,000) or small (e.g. 0.00001), then scale your data and plot it with a scale factor. For example, 100,000 would be divided by 1000 and plotted so that the maximum value would be 100 (“100” is more readable than 100,000)
Lab: Chem 219 Lab Report Guide date: 2/26/
- Use simple geometric symbols for your graph points: open or closed circles (e.g. ○●), squares (□■), triangles or inverted triangles
- Be sure your lines/curves are of appropriate thickness and line style (solid lines preferred)
- Annotate every key peak in a figure (see example that follows) Final important point: Be sure your figure is included at an appropriate size.
- If it is better to turn the page from portrait to landscape to make the figure bigger, do it
- Don’t try to jam several figures on a page by making them smaller
Lab: Chem 219 Lab Report Guide date: 2/26/ Figure 2. [Example of insertion of a Chem Draw figure. The next sentence or two would explain the figure.] *C O H *C OH NH 2 *C O *C OH O S *C O CoA S *C O CoA S *C O CoA HO O S *C CH 3 O CoA HO O OH S *C O CoA H 3 C O OH O CH 3 Leucine 2-Ketoisocaproic acid Isovaleryl-CoA 3-Methylcrotonyl-CoA 3-Methyl- glutaconyl-CoA 3-Hydroxy- 3-methylglutaryl-CoA Acetoacetic acid Acetyl-CoA *Glucose or *Glutamine
*C O 2
TCA
Cycle
*C O 2
Lab: Chem 219 Lab Report Guide date: 2/26/ APPENDICES #1. Give a title #2. Give a title If you have material that is relevant to your report in the form of complex spectra, long lists of data, etc that do not readily go into a making a simple table or figure, then these materials may be attached as appendices to the end of the report. List each piece of material with a sequential number and title.
