Feedback about lab notebooks

Now that I’m finished reading lab notebooks, I want to share a couple of general observations. The first and most important one is this: the lab notebooks were generally good. Most of them were prepared well, used effectively in lab, and succeeded as records of scientific work. Keeping a good notebook may not seem like much of an achievement, but it took a fair amount of time for you to read all of my instructions, consult the examples in Padias, look up data on compounds, and so on, so you have deservedly earned my praise. Well done.

Of course, I also saw some gaps here and there, but only three deserve special comment (I promise to be brief).
1. Hazards. While nearly all of you included some information about chemical disposal :-), many of you did not list hazard info. This isn’t acceptable. You must accept your share of the responsibility for keeping the lab a safe working environment. Here are two words that might help you in this task: hazard + handling.

A substance can present many types of hazard. Once you know the relevant hazards, you can list the appropriate methods for handling this substance.

Hazards generally fall into two categories, but there are many variations in each. A hazard can be due to chemical reactions with other substances in the lab (flammable, pyrophoric, corrosive, etc.) or it can be due to chemical reactions with substances in your body (toxic, irritant, stench, lachrymator, etc.). Many hazards are linked to a particular state of matter (toxic vapors, irritating dust); paying attention to this helps you understand how to handle this material. List any hazard that will lead to special handling. Then list the instructions for handling the material (store under nitrogen, gloves, fume hood, etc.).

2. There always needs to be a table of physical properties that describes all of the reagents you will use and all of the substances that you expect to make. The key physical properties are MW (molecular weight), mp (melting point), bp (boiling point), and d (density). These should be assembled in a compact, neatly written table (see Padias, p. 6). Try to fit this information onto a single page. It will make the information you want that much easier to find.

Note: Pure liquids and solutions are characterized by different properties. For example, if you are working with “3M HCl” or “saturated NaHCO3”, it doesn’t make sense to list the MW, mp, or bp. On the other hand, knowing the concentration of “saturated” NaHCO3 or “concentrated” HCl could be very useful.

3. This is the most important problem that I came across, but it only applies to a dozen or so students, so I saved it for last. The “procedure” section must contain a description of the operations you have performed, and not just the observations that you have made. It probably makes perfect sense to you when, in the middle of lab, you look down at your notebook and read “2-butanol, start 25 mL, end 24.5 mL”. However, it won’t make sense to anyone else (and, in another couple of weeks, it might not even make sense to you). Some action words are required: “added 2-butanol to water using a buret, start 25 mL, end 24.5 mL”.

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