Formal Lab Report Guidelines and Template
Updated for Fall 2021
Abstract:
In this first section, you will summarize the experiment. Science writing in general avoids personal pronouns (no I/we), and instead uses passive past tense to talk about what happened. The abstract should include the following information: what the objectives of the experiment were, how the experiment was performed, and what the key results were (percent yield) and what other techniques were used to analyze the results. Try not to include any procedure and avoid just listing the techniques. Try to answer “why” you used these things. If there is space, a concluding statement can be added. An abstract should be approximately 100 words.
Reactions:
Draw out the reactions that took place in this experiment. Any change that took place – from a full synthesis to a mere acid/base exchange of protons should be included. Use the readings and powerpoints to guide you if you aren’t sure what to include. Reactions must be drawn or created by you! Do not copy and paste from anywhere. This can be done in several different ways. (See Resources Module for more help).
Scheme 1. Synthesis of a thiourea . I added a short caption to this figure (just a line of text right under it in a smaller font) to describe the reaction conditions. You can do this to describe the concentration of a solution used or add details that aren’t drawn in the reaction scheme.
Chemical and Physical Properties
List all of the chemicals that could be measured in this lab (exclude intermediates) in a table like the one used in the pre-labs. You are welcome to copy the one you made in your pre-lab, but make sure it is updated to include everything it should have. Structures must be drawn by you – no copying and pasting anything. And make sure to include a source in a footnote.
Table of Chemical and Physical Properties
Name Structure Hazards Molar Mass (g/mol) Melting Point (°C) Boiling Point (°C) Density (g/mL)
Hit tab in last cell to create new row
Procedure:
In this section, a formal procedure for the entire experiment will be written. It should be detailed enough for someone else to repeat the experiment and get similar results, but it can be assumed that the person reading this is familiar with basic lab techniques. For instance, stating that a solid was recrystallized from ethanol and collected by vacuum filtration is detailed enough. Anyone needing additional details would make that a part of the lab notebook, not the lab report. If there is some sort of deviation from the standard protocol, then that detail should be included here. Notice how everything written is also in passive past tense. A procedure must have all of the exact values that were used in the experiment (from the notebook), all specific solvents that were used or the length of time something ran, and should list analysis techniques that were performed. If a series of similar reactions were performed, it is acceptable to describe the general procedure used and summarize differences in a table. It might also be necessary to write a general procedure for each group of similar reactions, depending on the differences.
Results:
The results (numbers, spectroscopy data, anything else) should be summarized here. I find that a table may be the best way to organize everything. Feel free to reuse anything that you did in the post-lab that you turned in, but! make sure that you look over it and revise it based on feedback from your TA or you may lose (more) points. Remember, this is an individual assignment so make sure you are using your work from the lab.
Include any calculations you do! You can write them out (take a picture/scan it, crop, paste it in, adjust the color, contrast, and brightness) or use the Insert Equations option, or some other alternative, as long as it is easy to read and follow what you did.
Discussion:
Use the questions asked in the Post Lab for the experiment to get a sense of the type of discussion that should be taking place. In addition, here are some general guidelines:
Start by looking back at the objectives for this experiment. Consider how each objective was completed. Talk about the overall mechanism and how the product was made. Look at the techniques used and discuss how these specific techniques gave these results. Discuss why these techniques were chosen, if they were successful, and what the limitations may have been. You are using this section to compare the theory of what should have taken place (what you see in the textbook) to the practical experience – how easy is this reaction or technique really? Just because it can be done doesn’t mean it is easy or works well all of the time. This is where you will discuss the percent yield and purity, as well as your IR and NMR spectra. This is where you will use the sources you found to help bolster your arguments. Don’t forget to cite them!
A discussion generally looks like this:
● What did you want to do
● How did you do it
● Why did you make those choices
● How would you know if you were successful or not
● Were you successful
● How could you do better next time
Questions you should try to answer:
Describe the mechanism for this reaction. Include the role of each reagent used and if any side products could have formed.
On percent yield: How was the product isolated? Are there any reasons some of it may have been lost? Do not ever say “human error” or some version of that. Should the percent yield be 100%? What would cause it to be high or low? If you say some amount was spilled or left behind in the glassware, think about what you are saying. Are you saying you left 50% of the solid behind?
On purity of solids: how exact are the melting points, are the ranges wide or narrow and what does that mean in terms of purity? If not pure, what (specifically) would be the impurity present? Poor technique should be your last possible explanation. There is usually a better reason based on the background information.
IR: assign peaks to functional groups in your product. Are there any extra (significant) peaks that would indicate an impurity?
NMR: assign each peak to each set of hydrogens in the product. Are there any extra peaks that need to be explained?
After you discuss what you did, how you did it, and why, move on to how you know if you were successful or not, then you want to conclude with what could be done differently in the future. How would you improve on these results? What does improvement look like? Is it a higher yield? Is it a more pure product? Is it both? Is it a more efficient process, or use of Greener chemicals or techniques? This will vary depending on the experiment, how it was done, and how well it worked out.
References:
List your references from the paper again at the end in the order they appear. If you were inserting footnotes, you will just go back and copy and paste the footnotes here. And then fix the formatting so the font size is correct, etc… Use ACS formatting.