CHE 423: Inorganic Chemistry
Laboratory
The lab notebook is your
evidence that you have done the assigned work.
All data are to be recorded in the notebook at the time that they are
obtained. Break the scrap paper habit now. All scrap paper will be
confiscated if seen by the lab instructor. The left side page of your notebook
is to be used for scratch work and for recording weights of reagents. Notebooks
should be seen in the balance room whenever you are weighing out something! Some
ideas for notebook recording are provided below to assist you as you begin
using a research notebook.
1. Leave room at the beginning of the notebook for a Table of
Contents, and keep it up‑to‑date.
2. If the pages in your notebook are not numbered, immediately
number all pages.
3. Date all entries.
4.
Start
a new experiment on a fresh page and record in ink. If you have begun a second experiment before the first was
completed, simply go to the next available empty page and finish the first. Be sure you
indicate the page number for
the continuation and the page where it is continued from. DO NOT
LEAVE ANY BLANK PAGES!
5. If the experimental procedure is identical to one described in the literature, it is not necessary to copy out the details of the procedure; simply cite the reference. If a published procedure is employed with some minor variation (i.e. amounts of materials used), cite the reference and note the changes you made.
However, if you used a
published procedure but made major alterations to it, or if you use a method
more‑or‑less of
your own design, it is best to write out a full experimental procedure. Use the right hand page to keep a
running record of what you are doing, how you are doing it and what is
occurring as the reaction is progressing.
The key is that
someone using your notebook
should be able to reproduce your result ...there needs to be enough detail
to allow for verification of
your experimental results.
6. Do
not attempt to delete information from the notebook, even if it is incorrect. Merely
draw a line through it and then amend it.
7. Completeness is more important than neatness. Being
complete means a competent student could use
your notebook as a guide to
repeat the experiment with only minimal checking in the literature.
8. Be sure to include the following:
a.
Introduction
or purpose (in addition to a title)
b. A balanced reaction equation for the reaction(s) to be
completed.
c. Table of reagents and products listing structure, mol.
wt., moles, and any physical properties
important to the experiment
(i.e., density, toxicity data, special handling procedures...)
d.
Yield
data (actual yield in grams and the % yield)
e. Observed properties of each product. Important data may
include m.p., b.p., color, crystalline
form, etc. The spectral
results should also be tabulated in the notebook and spectral
assignments should be made
in the notebook. The actual spectra should be kept in a separate
folder and significant
confirmations or questions of product identity noted on spectra and in the
notebook.
f. Method of purification. Oftentimes, the most difficult
step in the preparation of a compound
is not its formation but
rather its isolation in pure form from an initial product mixture. If
several steps are involved,
specify your purification procedure by means of a flowsheet.
g. Analytical data should be carefully recorded directly in
the notebook. Weights of materials used
to prepare analytical
samples must be recorded directly in the notebook along with the
appropriate units. Calculations
to confirm redox potentials, optical rotations, conductances,
molar absorbtivities, etc. ,
should be done directly in the notebook.
h. Final summaries for completed experiments can be added to
indicate the success or failure of
a given experimental method.
9. Writing style:
Although almost any sort of
coherent, legible writing style is acceptable in a lab notebook, it is best to
develop a habit of writing experimental procedures in the style commonly
encountered in scientific journals. In this course, use of this sort of writing
style is strongly encouraged. A rigorous treatment of this topic will be found
in the "Handbook for Authors" distributed by the American Chemical
Society.
Your lab notebook will be collected at the end of each section of the class to be evaluated. Attention will be given to when the entries were made (i.e., while working or three days later), whether there is sufficient information to allow someone else to figure out what you did, and inclusion of spectral data and analysis. Your instructors will no doubt wander by and look at your notebook at random unannounced times throughout the course to see how things are going and to make suggestions.