|
This page contains information on:
what to do BEFORE, DURING, and
AFTER a laboratory session.
BEFORE LAB
Prelaboratory preparation:
 | It is absolutely essential that you
prepare for the day’s experiment prior to arriving in the laboratory. The first step,
of course, is to read the experiment. Make sure that you read the entire experiment
including any peripheral material that you may find helpful (e.g. excerpts from your text
or some of the lab texts that can be found in Smyth 301 or the library). It is my
recommendation that you not only understand what is going on, but also why
you are doing the experiment. We definitely want your laboratory experience to be one of investigation
and discovery and NOT "cookbooking". A summary of preparatory steps follows:
|
- Read the experiment and any peripheral materials
(suggested reading)
- Write up your prelab in your laboratory notebook (more on
this in the next section)
- Think about the what, how, and why aspects of your
experiment
- Research and record physical properties of reagents and all
safety considerations (use the internet or the materials provided in Smyth 301)
- Perform necessary calculations
- Develop a game plan
- Prepare yourself so that you will be able to leave each
session with an understanding that you have learned a new technique that fits into your
overall laboratory expertise/repertoire.
Notebook format:
| Your laboratory notebook is your
personal guidebook. You will want to have it with you for every experiment. In fact,
it will be the ONLY resource that you can bring to the lab. For each laboratory
session, you will want to have the following:
|
- your laboratory notebook
- a calculator
- a pen (not a pencil)
- an EXCELLENT working knowledge of what you are about to do
and why you are doing it
| Some information should be recorded in
your notebook prior to coming to the lab. Some of the things that
you’ll want to do before coming to lab are:
|
- Create a table of contents on the first page of your
notebook.
- Number every page in your notebook.
- Write the title and the date of the experiment at the top
of the page in which the experiment starts.
- Write the purpose/hypothesis of your experiment.
- Write out the balanced chemical reaction (using structures)
if appropriate.
- Create a table of reagents which includes an exhaustive
list of each reagent’s physical properties (mass, moles, MW, density, mp, bp, IR
data, NMR data, solubility, safety considerations, etc.). --- SEE HELPFUL
LINKS PAGE ABOVE!
- Show all preparatory calculations (written out completely
with significant digits, units, etc.) including the theoretical yield (if appropriate).
- Prepare a procedural flow chart.
DURING LAB
- Work safely and efficiently in the lab.
- Take prelab lecture notes --- you will want to leave a
section for this in your notebook.
- Record experimental observations --- you may want to create
a section called "observations" and record within or find some way to coordinate
your observations with your flow chart (procedure).
- Record experimental results --- it is often helpful to have
a results section and record within a table. Results generally include the following: mass
of product (in grams), percent yield (show calculation), melting point, boiling point,
color/condition of the product, spectral data (IR, NMR), chromatography data (Rf,
retention times), miscellaneous graphs, results of qualitative tests.
- Experimental summary --- a brief one paragraph summation of
the experiment including relevant findings and a statement of the take-home message(s).
AFTER LAB
Laboratory follow-up exercises:
| I will hand out a series of
questions/directives at the beginning of each laboratory session. These exercises will be
turned in as indicated in the laboratory schedule. All follow-up exercises are to be
turned in by 5:00 p.m. on the due date. Late assignments will NOT be accepted.
|
| Click on the link above and it will take
you to the actual post-laboratory assignment.
|
The formal laboratory report:
The two formal reports that you will be
required to write should be formatted similarly to a manuscript copy of a publishable
journal article that would be found in the primary chemical literature. In this regard,
you may peruse some of the journals that we have here on campus (J. Org. Chem., J. Chem.
Ed., or J. Med. Chem.) or review the information that is found within the ACS Style
Guide which can be found in the Wilmot library. At any rate, your report should
include the following sections:
- The title of your report, your name, and the date – on
a title page
- An abstract – a one paragraph overview/summary of the
entire work
- An introduction/background section – relevant
background information should be introduced so that the reader can have a good
understanding of the context of your work. For example, you may wish to describe the
mechanism of the reaction (if applicable). Be sure to always include relevant structures.
- An experimental section – a description written in the
past tense, passive voice of the procedure/equipment used to carry out the experiment.
- A results section – tables, figures, diagrams, flow
charts, etc. that summarize your experimental data and results. It should be noted that
spectral data needs to be appropriately recorded. You may want to seek out an example form
the primary literature. You cannot simply attach spectra, graphs, etc. to the back of
your report.
- A discussion section – this section is by far the most
important segment of your report. It is a narrative summary of the work accomplished and
includes descriptions of how you arrived at your conclusions. In addition,
explanations as to why certain outcomes occurred are revealed.
- A conclusion – a one or two sentence wrap-up of your
experiment.
- A bibliography – any references consulted should be
listed here and appropriately annotated within the body of your report. Most students fail
to include appropriate references and often do not utilize correctly. Be sure that you
know how and when to use referenced information.
- Your laboratory report should not exceed seven (7)
type-written pages.
|
