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How to Keep a Notebook
One of the most useful skills you will acquire in the laboratory is the proper use of a laboratory notebook. Notebooks, or other formally kept records, are an essential tool in many careers, ranging from that of the research scientist to that of the practicing physician. The effort invested in developing good habits of notebook use will be amply repaid for students who pursue a future in the basic or applied sciences. Experience has indicated that skillful notebook use is developed by most students only through continued special effort--it does not come naturally. Some of the main principles of sound notebook use are outlined below.

The laboratory notebook is a permanent, documented, and primary record of laboratory observations. Therefore, your notebook will be a bound journal with pages that should be numbered in advance and never torn out. A notebook will be supplied to you before the first laboratory period. Write your name, the name of your TA, and your lab section on the cover of your notebook. All notebook entries must be in ink and clearly dated. No entry is ever erased or obliterated by pen or "white out". Changes are made by drawing a single line through an entry in such a way that it can still be read and placing the new entry nearby. If it is a primary datum that is changed, a brief explanation of the change should be entered (e.g. "balance drifted" or "reading error"). No explanation is necessary if a calculation or discussion is changed; the section to be deleted is simply removed by drawing a neat "x" through it.

In view of the fact that a notebook is a primary record, data are not copied into it from other sources (such as this manual or a lab partner's notebook, in a joint experiment) without clear acknowledgment of the source. Observations are never collected on note pads, filter paper, or other temporary paper for later transfer into a notebook. If you are caught using the "scrap of paper" technique, your improperly recorded data may be confiscated by your TA or instructor at any time. It is important to develop a standard approach to using a notebook routinely as the primary receptacle of observations.

Each week at the beginning of lab lecture, you will turn in your prelab problems from the manual for grading. Prelab problems not turned in at the beginning of lab lecture will be marked late. The calculations in the prelab problems are usually similar to the calculations in the labooratory experiment, so you may wnt to note your solutions to the problems in your notebook for further use. On weeks when a "data sheet" is indicated, use your results obtained in the laboratory to complete the data sheet and turn it in for grading. Your grade for each lab will consist of points for the prelab preparation and problems and points for the information presented on the data sheet.

Once or twice during the term, you will do a formal lab write-up of the experiment. This should contain sections 1, 2, 5 and 6 from the introduction of the manual (p. 9), as well as a theory and procedure section and should be word-processed. You will also need to include a title page. Please see the Formal Reports section of your lab manual for more specific information.

Your notebook should be your primary source of information. Everything you do in the laboratory should be included in your notebook, from procedure to calculations. When notebooks are examined, we will look for the following points in almost all cases:

• Prelab write-up that shows that you were prepared for lab before beginning the experiment.

• Data and associated graphs and calculations that quantitatively gauge how successful your laboratory technique was.

• Enough explanatory information so that someone else with your knowledge of chemistry could, from your notebook alone, enter the lab and repeat your work.

• Your discussion and answers to questions raised from time to time in the laboratory manual itself.


Aside from the prelab requirements, note that the majority of the calculations and notebook write up can and should be accomplished in "real time" - while you are in the lab, recording data and observations, and making calculations. Always bring a calculator to lab. It will be invaluable in making preliminary calculations and even for calculating final results while you wait for other things to finish.

A laboratory notebook should be legible, and data in it should be readily accessible, clearly labeled with units, and grouped in a logical way. The following outline is suggested for Chem 5 and Chem 6. A sample lab write-up for a simple experiment to determine the density of liquids follows the outline below. This sample is shown elsewhere on the ChemLab site.

1. Objective
State the purpose of the experiment along with a brief statement of basic principles involved and the method to be used.

2. Reference
Cite the source for the experiment. It will suffice to reference the page numbers of the Lab Manual from which the procedure comes.

3. Prelab Procedure Flowchart or Outline
Before coming to lab, summarize the procedure you will perform in a flowchart or outline. Examples of both formats are given in the sample write-up.

4. Sample Calculations or Analysis Flowchart or Outline
Before coming to lab, write in your notebook a description of the calculations that you will perform to analyze your data. This can be in the form of a sample calculation or a flowchart or outline. Note that in weeks when no calculations are required, this section is omitted.

5. Procedure, Data, and Results
Qualitative observations and quantitative data are best entered in a running commentary. This commentary should be recorded in the lab, as the experiment proceeds. High prose standards are not expected. If repeated measurements are made using the same procedure, a table provides the best presentation. If the experimental work is done jointly it must be noted and reported independently. Your notebook must list your co-workers and identify who did what.

You may write this commentary on the same page as your Prelab Procedure, in an adjacent column. If you use this technique, prelab and in-lab writing must be clearly distinguished.

Calculated results are also included in this section. Write your calculations clearly and include a brief explanation for each step. Remember to include units. If the same calculation is done repeatedly, write one sample calculation in your notebook and report the results of other calculations in a table. If an uncertainty analysis is part of your lab write-up, it should be included in this section, with sample calculations.

6. Discussion
A discussion of the experiment should include qualitative and quantitative comments on your results. Calculations of precision, accuracy, and possible explanations of any obvious errors may be appropriate. It is often helpful to collect your results in tabular form. Questions posed in the description of the experiment in the Manual should also be answered here. An example discussion for the density experiment is shown in the sample write-up.

Note that steps 1 through 4 will be done before coming to lab lecture for the week's experiment. Note, too, that a logical tabular form for your data will often be the clearest presentation, but that you should construct these tables in the lab, as you obtain the data, as part of step 5.
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