Electronic Lab Reports

The skills needed to prepare a proper of a laboratory report are an important part of the General Chemistry experience. Your laboratory report should be a clear and accurate record of your experiment's procedure, observations, and calculations as they happen.  These records of what transpires in the laboratory are critical to the practice of chemistry and other laboratory sciences. Thus, when you are done with an experiment and all of the chemicals used have been washed away, and all of the apparatus taken down, the report will serve as an infallible "memory" of what happened and how.  In the real world, they constitute the basis for:

  • Published results of investigations (which usually summarize laboratory procedures)
  • Verification and reproduction of important procedures
  • Determination of claims of discoveries and ownership of inventions
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    The major question to keep asking yourself as you prepare a laboratory report is this:  have I provided sufficient detail so someone else can reproduce what I did in the laboratory AND get the same result I did.  Do you think someone could successfully run the lab from your report?

    Laboratory reports are critical when unusual or unexpected results are obtained. Discoveries and inventions are extreme examples of unusual results. The acceptance of such findings by the scientific community generally depends on independent reproduction of the finding. A recent example of an irreproducible, unusual finding was the much publicized announcement of the production of large amounts of energy through "cold fusion".

    Think of your lab report as a 'blog'.  It should tell people what you hope to discovery during the lab, a detailed procedure you will follow, your observations of what happened, any calculations, and finally a conclusion. 

    Attendance:  Attendance at all laboratory meetings is required.  If you find you can not attend a given lab then you will have to use it as your 'drop lab'.  If you miss a second lab, a grade of zero (0) will be assigned.

    Submission Process:

  • Prior to lab you will carefully read the lab write-up.  Based your understanding of this, you will email me a 'Word' document containing the Purpose and Procedure (see more details below) for this experiment.  This is your 'ticket' to the lab, so I must receive and approve it prior to the lab.  Don't wait to the last minute to submit it!  We have had email problems in the past.  You also may have forgotten something, and need to resubmit before coming to lab.  I would also bring a copy of your Purpose and Procedure document to lab on a flash drive just in case.
  • During the lab, you will open your Purpose and Procedure document and start recording all of your data and observations into that document.  You should also bring in a digital camera or cell phone to record the experiment as it proceeds.  You may also be required to save screen captures of your experimental results which will be placed in your final report.  Before you leave the lab, you must email me a 'Word' document that now contains not only your Purpose and Procedure, but your Data and Observations as well.  You do not need to submit the photos and/or screen captures of the experiment at this point, you will include those in your final submission.
  • You now have four days to email me your finished lab report.  Use your data to complete the calculations.  Be sure to include any photos or screen captures; and make sure you place them BEFORE your conclusions.  Based on your results describe how successful your were in the lab.
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    There will be several other people in the lab and it is not always possible for everyone to have individual equipment. For example, several analytical balances are available. It is important to note which one is used in a weighing. It is important to note if different balances are used to determine initial and final weights. If more than one container of a reagent is available, is it important to note if samples of the same material are taken from different containers?

    A student laboratory report should permit the determination of what step or steps in a procedure may have introduced discrepancies (e.g., when unknowns are involved, or when different results are reported on the same known material).

    Information that each lab report should contain:

  • Title:  The title should be as brief and as informative as possible.  Titles should also be included for all drawings, charts, or graphs.
  • Purpose:  The purpose should include a paragraph or two in your own words explaining what you are specifically attempting to determine and the method you are using.  Be sure to include all pertinent balanced chemical equations and diagrams of any apparatus you will be using.
  • Procedure:  This should include a concise step by step outline of what you actually must do to perform this experiment.  Explicitly note any alterations your instructor may make in the procedure.  The easiest way to generate this is to 'cut & paste' it from my write-up.
  • Observations: Include all numeric data obtained during the experiment.  Label all numeric data clearly with units and significant figures.  Also include detailed descriptions of all pertinent physical or chemical processes that you observe.  If you are using data from another student, clearly indicate that.  To receive full points, you will need to include several photos of your experiment in progress.
  • Results:  Label all numeric results clearly.  Include, when appropriate, any final values obtained, standard deviations of measurements, and percent error, when a theoretical result is available.
  • Conclusion:  Did the experiment work?  Remember the 'Purpose' told everyone what we intended to see.  Did you see that or did something else happen.  If the results were not as expected, suggest possible causes of the errors.  The conclusion should have scientific and practical significance.  It should not be a personal comment such as "this experiment was fun."  A statement such as, "this experiment was successful," is unacceptable without further explanation.  List possible sources of error, and explain whether they would lower or raise numeric results.  If you have suggestions for improving the experimental procedure, you should include them as well.  Remember, the 'Conclusion' by its very nature means that nothing can follow it!  Do not put data, calculations, graphs or photos after the 'Conclusion'.
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    Each of these sections must be separate and labeled. You must have the experiment purpose and procedure written prior to the laboratory session for each experiment.  Leave a little space in case the procedure must be modified from that found on the internet.

    Laboratory Grade:  Your laboratory grade represents 30% of your overall course grade.  You will be conducting eleven experiments and taking a comprehensive laboratory final.  The majority of your lab grade will come from your lab reports.  I will average the best ten lab reports and this will  represent 25% of your lab grade.  So you will have one 'drop lab' which will be your lowest grade or on you had to miss.  The other 5% will come from a comprehensive lab final.

    Grading of the Lab Reports:  Your laboratory report consists of a 'Word' document that will be sent to me three times (see Submission Process).  Each report is worth a total of 100 points which will be distributed as follows:

    A typical laboratory report is shown below:

    (click on each thumbnail to see the full page)





    (Updated 5/15/08 by C.R. Snelling)