Introduction
5
Chemistry Lab Report Format
Unless instructed otherwise, you will be expected to write a lab report in a prescribed format for
all lab experiments in Chemistry this year. Every lab report should include the following sections:
Title, Purpose, Data/Observations Table, Analysis, Results Table and Conclusion.
Occasionally there will also be a Prelab Assignment that will be required. Except for the
calculations and chemical equations required in the Analysis, the lab report should be done
entirely on the computer. If there is something wrong with your printer, email a copy to
yourself and print it at school, or email your teacher a copy. The calculations and chemical
equations can be done by hand on notebook paper.
Complete the report in three stages:
1. Prelab: This should be prepared as part of your homework before class. It will be checked at
the beginning of the period. At your teacher’s discretion, if you do not have a complete
prelab, you will either:
immediately lose up to five points from your lab score
or
not be able to begin the lab until your prelab is completed
A. Read the entire lab handout in your Study Guide before the experiment. You may
want to use a highlighter or underline the procedural steps. Study the information
carefully because a short quiz may be given covering the information in the
background, procedure and/or analysis.
B. Start with the title of the experiment (just copy it from the handout), your name and the
date of the experiment. If you are working with a partner, include your partner’s name
at the beginning of the report.
C. Write a brief (1-2 sentences) purpose indicating the objective of the lab. What
quantity are you trying to generate? What principle are you trying to investigate? The
purpose and the title are not the same thing.
D. Prepare a table for recording your data and observations. Data are measurements
such as “8 cm” and observations are descriptions such as “yellow light.” The table
should be labeled with proper headings and units. You should allow enough room in
your table to make corrections.
E. Many labs have a prelab assignment that requires you to balance some equations, do
some calculations etc. before you come to lab. A few of the 2nd semester labs ask you
to devise a method.
2. Collection of Data and Observations: This should be taken as you do the experiment. Your
data is your work. You should not use anyone else’s data unless instructed to do so by
your teacher.
A. During the experiment, record your data and/or observations in the table(s) you set up
in your prelab.
B. Be sure that all data is labeled with the proper units and recorded with the correct
number of significant digits.
