LABORATORY
NOTEBOOK
A lab notebook will be provided on the first day of class after you check in to your locker. Please leave the first three sheets blank for a title page and table of contents. You are required to number the pages in the notebook (you may number all odd or all even pages). All entries in the laboratory notebook should be written in non-water based permanent ink. Absolutely no pencil, erasures or white out. If you need to make a correction in your notebook, simply cross out the error so that the text can still be read, then initial the change. Always start an experiment on a new page and leave at least one page for class notes.
All the records and observations in your notebook will be used to evaluate your laboratory understanding and ability. Importantly, this will also help you to learn and improve your analytical writing skills. Answering questions at the end of each experiment will help you to think critically and have a better understanding of the laboratory experiments. Keep a well-organized notebook since you will use this notebook for your lab final.
For each of the lab reports, two initials of the instructor are required.
A laboratory report should have the following sections:
I. EXPERIMENT TITLE AND DATE
II. PURPOSE
III. BALANCED CHEMICAL EQUATION (if appropriate)
IV. PHYSICAL CONSTANTS AND SAFETY CONSIDERATIONS (parts III and IV may be combined)
V. PROCEDURE (This must be written in your own words)
Instructor’s
initial
VI. DATA AND OBSERVATIONS
Instructor's
initial
VII. RESULTS
VIII. DISCUSSION
IX. CONCLUSIONS
The first five items will need to be completed before you come to lab, and your instructor will need to initial these sections before you start the experiment. Before you leave the lab you need your instructor to initial the data and observations section. A brief description of some of the items is below.
II. Purpose: This section should be brief, one or two sentences, describing the main objective of what you are being asked to perform in this experiment.
III. Balanced Chemical Equation: A complete balanced chemical equation showing all reactants, products, catalyst, solvents, and reaction conditions is given using structural formulas. The necessary physical constants of the reagents including the amount used and the number of moles used should be given below the chemical equation.
0.2 g 2 mL
mp 122-124°C 1M Br2/CHCl3 mp 238°C
MW 180.25 g/mol 2 mmol MW 340 g/mol
1.10 mmol
IV. Physical Properties and Safety Considerations: List the physical constants of compounds that are needed to perform or interpret experiments, for example molecular weights, densities, melting points, boiling points, etc. Don’t list all of the physical constants that you can find but only list the physical constants that you need to do the experiment. In the first semester, it is easier to organize the physical constants in a table format, see below. For the second semester, you will run a lot more reactions; therefore you can organize the physical constants as shown in the above section with the chemical equation. List the hazardous properties of the compounds and this will help you to be aware of the hazard of the compounds that you are working with.
Some of the physical constants might be given in the procedure. Additional physical properties can be found in the Aldrich catalog, the Merck Index, the CRC Handbook or online. All these books are in the library reserve.
|
Compounds |
MW |
mp (°C) |
bp (°C) |
d (g/mL) |
Safety Considerations |
|
Anthracene |
|
216-218 |
|
|
|
|
1,1,1-trichloroethane |
|
|
74-76 |
|
hydroscopic |
|
Cyclohexane |
|
|
80.7 |
|
flammable |
V. Procedure: The Procedure should be either typed or handwritten. Follow the procedure given, be sure to include all of the relevant information. Ask yourself as you write, "Could someone else follow my procedure and get the same results in a timely manner?". As you perform the experiment, make any necessary changes to the procedure.
Don’t
forget your instructor’s initial.
VI. Data and Observations: This section should contain all the measurements and observations that you obtain from the experiment. Record everything that you see and do. For example, does the color change? Is the reaction releasing heat? What is the temperature of the sand bath? Etc. It is very important that you record everything as it happens so that you don’t forget the information after you leave the lab.
Don’t
forget your instructor’s initial before you leave the lab.
VII. Results and Discussion: The results section will include any graphs or calculations performed as well as the analysis of important data.
VIII. Discussion
The purpose of the discussion is to interpret and compare the results. For this section, list all the important factual information that you obtain from the experiment and then discuss these factual results. For example, report the experimental melting point, % recovery or % yield, etc and then compare this with the literature value and derive a conclusion from this result. For some of the experiments, your instructor might indicate a focus of the discussions. The discussion may also answer the following questions:
What did you expect, what actually
happened and why did it happen?
Can you explain the differences
between your expectations and the actual results?
What are the errors or limitations of
your techniques, equipments, the procedure itself, etc.?
What did you learn about the chemistry,
and how could your results have been improved?
If you have to repeat the experiment, what can you do to improve the
experiment?
For this section, you will be graded for the completeness and clarity of your arguments. Grammar and spelling are very important. You should write in clear and concise sentences. An instructor may ask you to type, cut and paste this section into your notebook. Importantly, do not rewrite the experimental procedure in this section.
BE SURE TO REFERENCE THE RESULTS AND DATA THAT SUPPORT YOUR CLAIMS.
IX. Conclusions: This section should be brief. The objective of this section is to put the interpretation of experimental results into the context of the purpose of the experiment. Don’t repeat the discussion points.