A lab report is a document which describes a scientific experiment. It provides a formal record of the a hypothesis and the methods and outcomes of the experiment, using clear, precise language. Enough detail should be given to allow the reader to replicate the experiment if desired.
The exact format may vary, but the typical lab report follows a specific format and has specific sections covering different areas of the experimental process. These are:
This is the front page of the document. It gives the title of the experiment, the name(s) of the experimenters, the date, and the course the report was written for (if applicable).
The abstract is a brief summary of the report. It should be short (1 paragraph of usually no more than 200 words) and tell the reader your hypothesis or the reason for conducting the experiment, your methodology, your results and your conclusion.
In this section, you present the objective of your experiment and/or your hypothesis, and give the reader the background information necessary to understand your experiment (in order to do this, you may need to refer briefly to the literature on the topic. If you do this, make sure to properly cite your sources!)
This section may be called either Materials and Methods or Procedures, but in either case, the content is the same. Here you describe the methodology of your experiment: what you did and what materials you used to do it. It's important that you be very detailed in your descriptions so that the reader could replicate your experiment. Information such as exact measurements, temperatures, and timing are important.
Now it's time to present the results of your experiment. What data did you gather? Did anything unexpected happen, or did anything go wrong? Usually, tables and graphs are used to present data in a more precise, clear manner.
Here is where you show your understanding of your experiment. Use this section to describe your observations during the experiment, and discuss your findings in relation to your hypothesis and to the literature referenced in the Abstract. If the experiment failed or you experienced problems during the experiment, discuss what might have caused this, and how it might be rectified in future experiments. You may also raise any questions that are suggested by the results, and discuss how these questions might be answered.
In this final section, cite any sources you used in the experiment. These should be full citations, using the citation style recommended by your professor (if your professor does not require a particular style, you may use a style that is commonly accepted in your discipline).
Laboratory Report Instructions (Doyle Online Writing Lab, Reed College)
Writing Lab Reports or Research Reports (University of Guelph)
The Lab Report (University of Toronto)
LabWrite (North Carolina State University & the National Science Foundation)