Lab Report Format - Cary Academy

Procedure Sheets
• Include sheets provided or a detailed procedure that you have written yourself if
none was provided.
Data and Observations
• Use this heading to organize this part of the report. (The remaining sections may
follow each other in order on the same continuing page.)
• Present quantitative data in well-organized tables. All measurements should
incorporate proper use of significant figures and unit labels.
• Qualitative observations can be written in paragraph style under the tables.
• Accompanying graphs can be included here when appropriate.
Calculations and Questions
• Use this heading.
• Label calculations (What are you calculating? What are these numbers?).
• Include units with measurements and the identity of the substance if applicable.
• Show all work, beginning with an original equation if one was used.
• Pay attention to significant figures and rules of rounding.
• Answer in complete sentences when the question involves discussion. The reader should
know what the question was about by reading your answer.
Results and Discussion
This section can usually be one paragraph. In the first sentence, restate the results of the
experiment. Secondly, state the accepted value if there is one. Third, indicate the quality of
your results by re-stating your percent error, percent yield, etc. Finally, analyze your data
and results by conducting an error analysis. Was your percent error high or low? What are
the suspected sources of error? How did the error affect the original measurements (data)
and how will that compromise your calculated results? Be insightful. The logical thinking and
analysis required here are important skills in most jobs. Discuss sources of error that are
legitimate and relevant to the experiment. Unsubstantiated human error, equipment error,
etc. is not acceptable. In other words, you cannot attribute your error to "we must have
massed something wrong". If you know you massed something wrong or your data suggests
that you did, explain and support your conclusion. You must cite specific and concrete
sources of error. A helpful hint to writing a good error analysis: take careful notes
of all errors or suspected errors as you carry out the experiment. Don’t rely on your
memory for discussion of error when you are writing your lab report later! Document as you
go! Finally, make a solid connection between what you did, the results you got and any error.
Other suggestions:
• Always read the lab, paying careful attention to the procedure, before the lab begins.
• Results, per se, will not be graded for accuracy, but you must be able to explain reasons
for your error. Calculations must be correct.
• Quantitative labs must have quantitative conclusions (see above).
• Cleaning up the lab is everyone’s responsibility! Points will be deducted for failure to do
your part!
• When in doubt, ASK! I’m here to help!