Following Lab

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Taken from:
http://www.foothill.edu/psme/armstrong/labnotes_12B.shtml
Organic Chemistry Lab Reports
Lab reports should be completed for each experiment in the laboratory
notebook, and a copy of the pages for each report turned in one week
following completion of the experiment (unless otherwise specified).
All data and pre-lab work should be written directly in your lab notebook in
blue or black ink. No scratch paper is allowed at any time. Points will be
deducted from your report grade if you forget your notebook, if you write in
pencil, and/or if you record data on scratch paper. To download an pdf
example of one student's pre-lab click here.
If there is not Table of Contents in your notebook, leave 5-6 pages blank at
the front of your notebook. Write as neatly as you can. Word
processing/Spreadsheet use is required for the Post-Lab entries, and
hardcopies must be stapled into the notebook.
YOUR NOTEBOOK MUST CONTAIN COPIES OF ALL DATA INCLUDING GC TRACES/
SPECTRA AND POST-LAB WRITE-UPS.
Before Lab complete the following entries:
these will be collected or checked individually at the beginning of each lab. If
the entries are not complete at the start of the laboratory lecture then they
are considered late.
1.
2.
3.
4.
Title
Purpose
Reaction(s)
Mechanism*
*Unless an exception is made by your instructor, include the net chemical
reaction under investigation and its mechanism using curved arrow
formalism. If the mechanism is not provided in the laboratory text, you must
look it up in your lecture notes or textbook. You must include any
mechanism that is given in Smith or Mohrig even if it has not yet been
discussed in lecture.
5.
Table of Reagents, Products and Solvents
A tabulated list of the names and properties of reactants consumed during
the reaction (or those needed in a limiting reagent calculation), along with the
major organic product(s) formed, and all organic solvents. Include in the
table molecular weights, densities and boiling points of liquids and the
molecular weight and melting points of solids. In addition to the physical
properties, include the safety hazards and handling recommendations of
each entry. Do not include drying agents, inorganic salts, acids or bases
unless they are unfamiliar to you, in which case you ought to look up their
safety information. Safety information can be found on MSDS sheets in the
stockroom, or online (for example at Chemfinder.com). See your Techniques
book (Techniques 1 and 4) and your Laboratory Guidelines handout for more
information.
6.
Determination of limiting reagent/Theoretical yield calculation
This is required for any preparative experiment. You will be marked off if this
is done incorrectly. See Technique 3 in Mohrig for a review.
7.
Procedure
An outline form of the Procedure (preferably on the left side of the page so
that data and observations can be recorded next to each step). The outline
should not be a verbatim copy of the laboratory text. Include what is done
but not how it is done.
8.
Pre-Lab Assignments
Check each experiment for pre-laboratory assignments. These are distinct
from pre-lab questions (which are related to the purpose of the experiment
and are simply the questions under investigation) and post-lab questions (or
“Questions”) that follow the procedure in the textbook.
During Lab:


Date
Partners Names

Data/Observations Aside from required temperature and mass
readings you must include observations made during the course of the
experiment.
Record any “mishaps” which take place during the experiment must be
reported. Points will be deducted if they are not recorded.
Experimental Conditions (Instrument settings, etc.)
If a partner is recording data, you must transfer the data to your notebook
before the end of the lab period in which it is collected.
Following Lab:
9.
Summary Sheet:
You will be filling out a "summary sheet" for each lab. These summaries must
be typed, and include the information such as:

Tabulated Summary of Data
Discussion of Results
Be as specific as possible in specifying results that lead you to your
conclusions. All results should be in your data section, and are merely
restated here

Calculations
Any relevant calculations.

% yield calculations (Technique 3.2) and/or % recovery
calculations.

Analysis
Some inquiry-based experiments require an analysis of the results to answer
a question. For example, which product is formed in greater yield and why?
A discussion of your analyses should be recorded in this section.

This section must include a discussion of the information gained from the
experiment and an analysis of its pertinence to the purpose of the
experiment. Specific reference to data and its explicit comparison to
literature data is expected here whenever possible. Literature data must be
explicitly given and referenced. For example, product mp should be
compared explicitly to literature mp (Recrystallized product MP = 130-133°C;
Lit (Aldrich) MP = 135-137°C)) in every experiment in which a solid product is
produced. Sources of error should be addressed in this section as well.
10.
Questions
Post-lab questions are not graded but are highly recommended as
preparation for the lab exams.
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