Chemistry/Mrs. Basile
Name:_________________________
How to Write a Lab Report
Format: Typed, in 12-point font, correct spelling and grammar, using past tense passive voice. It does not
need to be double-spaced, but should have a blank line between each paragraph and/or section (as shown
in this handout). Put your name in the header, followed by the names of your lab partners, the period, and
the date.
Example:
Nicole Basile
Lab Partners: Jodie M.
Christina G.
Period 1
8/27/12
Title: Short, to the point, may or may not be the same as the handout.
Purpose: Restate in your own words. DO NOT copy the purpose exactly from the lab handout. This
should be a complete sentence. For example, “The purpose of the lab is…” or “The goal in this lab was
to…”
Procedure: Summarize the procedure. You do not have to write it out step by step. It should be in
paragraph form and in past tense passive voice. “First, the mass of the solid was measured. Then the
volume was found by using water displacement…” You can assume your audience has some
chemistry/laboratory knowledge and would understand common procedures and terms such as water
displacement, titrate, etc. Especially note any changes or deviations from the lab procedure. For example,
if the lab handout said to use 20 mL of water, but you used 25 mL, you should include that information in
the procedure section.
Data: Any qualitative observations may be in paragraph or tabular form. Put your quantitative data in
tabular form (in a table) to make it easier to find and identify the data. Make sure you include appropriate
units such as grams, milliliters, centimeters, etc.
Calculations: You should show how you did any calculations. Make sure you include appropriate units and
your answers are rounded to the correct number of significant digits.
Graphs: All graphs should include a title, both axes labeled with units, and a legend or key. (Not all labs
will have a graph.)
Analysis: The analysis should include answers to any lab questions, written in paragraph form. The
answers do not need to be in the same order as in the lab handout, but answers to all questions should be
included. This is where you synthesize what happened in the lab and what you discovered. For example,
“The density of the liquid was determined to be 1.0 g/mL and therefore the liquid is water.” Explain the
scientific concepts involved in this lab.
Conclusion: In this section you summarize what you have learned in the lab. What errors were made?
What could you do better if you did the lab again? What would you change if you did the lab again? Did
you achieve the goal/purpose of the lab? Include improvements on lab itself-not how you did the lab.
Comment on how the lab is set up, do not say “the volume may have been measured wrong”; instead say
something like- “the volume should have been measured with a graduated cylinder rather than a beaker
because it is more precise.” Why are those errors important/relevant, how would they affect the results?
Chemistry/Mrs. Basile
Name:_________________________
Sample Rubric for Density Lab:
Lab Report Rubric: Each bullet is worth 2 points. Each section must be included AND
correct to receive full credit.
□ Format: followed directions
□ Purpose
□ Procedure summarized, not step by step
□ Procedure written in past tense passive voice in paragraph form
□ Data tables included
□ Data tables include appropriate units
Calculations demonstrated with formulas
o Density of water
o Density (slope) for unknown liquid
o Density of solid
□ Calculations include appropriate units
□ Identity of unknown liquid
□ Graph: axes labeled, title,
□ Graph: set up and drawn correctly
Analysis questions
o All solids?
o Why is part B better?
o Calculate volume
□ Conclusion: summary made
□ Conclusion: errors discussed
□ Concludsion: improvements suggested
□ Conclusion: did you achieve goal/purpose of lab?
Comments:
Total: ______________ out of 40