How to Keep a Laboratory Notebook
Laboratory notebooks are legal archival documents where scientists record exactly
what they did and observed for a given experiment on a given day. Lab notebooks should
include a detailed account of experimental procedures (or reference to procedure) and all
raw data collected.
All laboratory activities must be recorded in a complete and well-organized manner in a
bound notebook with consecutively numbered pages. Below are guidelines for how to keep
a good laboratory notebook. While the organization described in these guidelines is
important to adhere to, keep in mind that notebooks are documents scientists write AS
THEY ARE WORKING, and thus no one expects them to be perfectly organized, neat, or
error free. Writing observations, on scratch paper or outside of the lab period and recopying your notebook pages to make them “prettier” is not appropriate.
1. On the Front cover should be your name and the course number.
2. On the inside of the front cover should be your locker combination, and contact
information in case you lose your lab notebook
3. The first page should be a map of the lab where hoods, safety devices, broken
glassware depository, waste disposal, are clearly labeled.
4. Leave the 2-3 pages of your notebook blank, for use as a Table of Contents.
5. When writing in your notebook:
a. Always use ink
b. Write legibly using simple declarative sentences
c. Write directly in your notebook, not on a piece of paper first
d. Never use white-out. If you make an error simply draw a line through the
mistake, and re-write the correct text. For example: 2.908g 2.928g
e. Do not cut and paste documents into your laboratory notebook
f. All experiments must be written in your notebook on consecutive pages
6. NEVER remove notebook pages.
7. If you use a computer for data analysis (i.e. Graphs), include a sketch of the graph
on the notebook page in the “Results” section. Also include the name and location
of the corresponding computer file.
8. You will need to include the following elements: Sections A-E should be created
before lab. Section F should be created during lab, and Sections G and H,
Results and conclusions should be written after you have collected and interpreted
your data, usually at home.
Lab Notebook Contents
A) The date, and experiment title.
B)
The “Purpose” section. In one or two sentences, summarize what the
experiment should accomplish.
C)
Method section: Scientific principles used to carry out the experiment
stated.
D)
Equation section. For experiments involving chemical reactions provide a
balance equation. Give the name of each reactant and product, and create a
table listing the physical data such as molecular weight and density. Also
create blanks for moles used, grams used, and mLs used.
E)
Procedure reference. Writing the entire procedure from the lab manual is
not necessary, but a reference to the procedure in the lab manual is required.
Any deviations from the procedure listed in the lab manual should be stated.
F)
Data section. Record all data. The date section should always contain
both qualitative and quantitative data: Qualitative data consists of observed
(colors, color changes, temperature changes, formation of precipitates, gas
formation, etc.), and deviations from your stated procedure. Quantitative data
consists of measurements and their respective units, with proper number of
significant figures.
G) Results and Calculations section. In this section, to be done usually
at home. All work must be shown for one of the trials. Required results should
have a square box around them with proper significant figures and units. The
required results should be also summarized in a results table, of your own
design
H)
Discussion/Conclusion: In his section the purpose should be restated
clearly showing if the purpose was achieved. For example if the purpose was
to measure the density of aluminum, you should state that the density was
determined to be 2.78 g/mL, with a percent error of 5.1%. Reasons for the
variance of your result with the literature value should be included, as well as
how you could improve in results when preforming the experiment again.
Your instructor will grade your laboratory notebook before
leaving lab.
Note:
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PreLab questions/problems are due at the beginning g of the
lecture period of the lab day on notebook paper and not in your laboratory
notebook.
Post Lab questions are not to be included in your laboratory
notebook, but in your lab report the following week.
Late work will not be accepted, so please do not ask. If you are not
going to be in class then please send your work via the e-mail
(tom.schultz@seattlecolleges.edu)