LAB REPORT GUIDELINES
PLATA
INFORMAL LAB REPORTS:
Pre-lab, purpose, procedure, data table and calculations will be completed in your lab notebook.
PRE-LAB:
Is not always part of the activity but when it is, it needs to appear before the purpose.
PURPOSE:
In your own words, what is this lab designed to teach you or help you investigate. You will also include any
hypotheses in the purpose unless you were already asked to make one in the pre-lab. Not every activity will require a
hypothesis.
PROCEDURES: Someone looking at your lab notebook/report should be able to reproduce the experiment based upon
your procedure. Especially for labs for which you need to write your own procedure, you need to be very detailed.
There will be times when writing a procedure will not be necessary or the procedure will be abbreviated.
DATA / OBSERVATIONS :
Arrange data in tables if possible. At the head of each column or row include names and units for the data. Record
numbers to the correct uncertainty and significant figures. Include uncertainities for measurements (either in the
column heading or with each piece of data). Qualitative observations should usually be included in sentence form
below the data tables. A part of the qualitative observations should be possible sources of error: both human (oops we
know we did this) or experimental ( volumes will be less naturally because ...) Make the section neat and easy to read.
CALCULATIONS:
Calculations should include units and should show the final answers to the correct number of significant figures. First
write a brief statement identifying what you are calculating. Then, if applicable, show the general equation (just once
if you are doing multiple calculations of the same type) if applicable. Finally, substitute actual lab data and show
calculations for all trials. If you have multiple trials, you only have to show the general equation once but you must
show all the data within the various trial calculations.
Example:
Density of sample
D = Mass/volume
D = 23.41 g = 1.59 g/cm3
14.7 cm3
You will then tear out the carbon copy of the pages from the notebook and attach it to any analysis and
conclusions that you need to create.
Analysis Questions and concluding statements will normally be typed on a separate piece of paper and
stapled to the back of the lab notebook pages.
ANALYSIS QUESTIONS:
Answer analysis questions in complete sentences so that the important part of the question is incorporated into the
answer. The answer should stand on its own without the reader needing to go back and re-read the question from the
lab instructions
For example:
Question: What colors were the precipitates that were produced during the reactions?
Good Answer:
Precipitate colors included white, pink, and brown.
Bad answer: white, pink, brown
-orThey were white pink, and brown.
CONCLUDING STATEMENT:
Be sure to reiterate the final answer from the lab if it is applicable. For example, each group was given an unknown
sample to identify. Your concluding statement would be something like: "I determined that unknown D was silver
nitrate." Always remember to include the unknown ID clearly in your lab report
FORMAL LAB REPORTS:
GENERAL GUIDELINES:
 Many parts of the lab that were done in the lab notebook, will need to be reproduced in a formal lab report.

Please type Lab Reports on white paper and double-check for errors before submitting them. PLEASE CONSERVE
PAPER. Print the lab on both sides of the paper. Make margins, etc. small so you use less paper. However, nothing
smaller than 10 pt font (except in data tables) please.

Lab reports should use proper English and sentence structure. They should contain NO abbreviations for words (such
as w/ for the word with).

Lab Reports should be arranged in the order presented in this document and should be stapled (stapleless or metal) in
the upper left corner (please no paperclips or other fasteners).

Title of the lab should appear at the top of the paper. Your name should appear in the upper right corner or just below
the title.

Your lab report must be completely your work. Your data will likely be identical to your partner’s, but that is
where the similarity stops. You may work with other students to review answers, offer constructive criticism, and
explain concepts to each other. However, once you are done discussing, the answer must be in your own words.
INTRODUCTION (FORMAL ONLY):
The introduction is designed to give background as well as a purpose for the report. You may briefly state the purpose such as:
“We will
(do) and (observe) so that we can
(conclude) .” or something like that. Following the purpose
you should offer background on the type of chemistry that the experiment included. Include terms and definitions pertinent to
the lab as well as general explanations of the science behind what you will be studying. Do not include any results. The
introduction is general. The discussion is where specifics from the experiment are discussed. If there is a hypothesis, it will
also be placed in the introduction.
DATA / OBSERVATIONS : follow informal report guidelines as part of formal report
CALCULATIONS: follow informal report guidelines as part of formal report. We will learn how to create mathematical,
chemical formulas and chemical equations on the computer as the year progresses. You will be expected to
type all calculations for your formal reports.
ANALYSIS QUESTIONS: follow informal report guidelines as part of formal report
RESULTS / DISCUSSION (FORMAL ONLY)
Within this section you should cover several areas. You want to summarize the answers to the big questions which the
“purpose” said the lab would answer. As you do so, you should include specific results from the lab rather than generalizing
the information. Go beyond restating the purpose and indicating that you addressed it. If the purpose of the lab was to
determine the density of an unknown rock sample, then you write that “the density of the rock sample was 1.59 g/cm3”. Do not
just say that “we found the density of the rock”. You want to include any sources of errors (both reasonable human and
experimental). Saying our calculations could be off is not a reasonable source of error. Calculate percent error when possible
and if not done in the analysis. Address any significant points raised in the analysis questions and restate them and their
significance to the overall experiment. You can distinguish yourself from other students in your discussion if you demonstrate
that you truly understand the “big picture” of the lab.