Organic Chemistry Lab CHM 258
Spring
Semester, 2007
9:00
AM – 12:00 PM T Maloney
3:00
– 6:00 PM W Maloney
2:30
– 5:30 PM R Maloney
2:30
– 5:30 PM F Tahmassebi
Instructors: Name, Office,
Phone Number, e-mail
Dr.
Maloney, Science Building 432, 481-6295, maloneyv@ipfw.edu
Dr.
Tahmassebi, Science Building 484, 481-6297, tahmassd@ipfw.edu
Text: Introduction to Organic Laboratory Techniques a small scale approach, 2nd Edition, by D. L. Pavia, G. M.
Kriz, G. S. Lampman, and R. G. Engel, Saunders College Publishing, 2005
Notes: CHM
258 website
Tentative
Schedule of Experiments
|
Experiment |
Title |
Reference |
Extra |
|
1 |
Oxidation of Cysteine to Cystine (Synthesis, 20 pt.) |
Handout |
|
|
2 |
Stereochemistry of the Addition of Bromine to trans-Cinnamic Acid (Synthesis,
20 pt.) |
Handout |
|
|
3 A |
Coenzyme Synthesis of Benzoin (Synthesis, 10 pt.) |
|
|
|
3 B |
Benzil (Synthesis, 10 pt.) |
|
|
|
3 C |
Tetraphenylcyclopentadienone (Synthesis, 20 pt.) |
|
|
|
4 |
Isolation of Essential Oils by Steam Distillation ( Analytical 20
pt.) |
|
|
|
5 |
Nitration of Methyl Benzoate (Synthesis, 20 pt.) |
|
|
|
6 |
Chiral Reduction of Ethyl Acetoacetate; Optical Purity Determination
(Synthesis, 20 pt.) |
|
Technique 26, pp. 909 - 915 |
|
7 |
Carbohydrates (Analytical, 20 pt.) |
|
|
|
8 |
Combinatorial Chemistry (Analytical, 20 pt.) |
Handout |
|
|
9 |
Identification of an Organic Unknown (Analytical, 40 pt.) |
|
|
Grading
|
9 Reports |
220 points |
|
Technique |
15 points |
|
Notebook |
65 points |
|
Quizzes |
50 points |
|
Total |
350 points |
Course Cutoff’s
|
A |
> 90% (>315) |
|
B |
> 80% (>280) |
|
C |
> 70% (>245) |
|
D |
> 60 % (>210) |
|
F |
< 60% (<210) |
Generally the grades
tend to be A’s, B’s and C’s. This is only true if all reports are turned
in as complete as possible, and the notebook is complete! Then D’s, and F’s become very likely!
Although I have been somewhat slow returning graded
reports in the past, you should know how you are doing after the midpoint of
the semester. It is up to you to keep track of your
grade and performance.
I will rarely make a point to tell what your grade during the
semester. Dr. Tahmassebi may handle
things somewhat differently. He will
inform you of any differences in their teaching styles. In any event, your final grade should not
come as a surprise. If for instance, you
are receiving a B by the ¾ mark in the semester, and continue to turn in all of
the reports, the reports are complete, and you don’t do poorly on the final,
then you will receive a B. If however
under the same circumstances you don’t turn in 1 or 2 of the final reports,
turn in other reports that are incomplete, and do poorly on the final, then you
could possibly receive a D or F.
Although there have been few D’s and F’s in this course, it has happened
and for that reason.
There
will be no lab final this semester. This
is what we have commonly done in the past.
Notes About This
Course
Tentative Schedule of Experiments
The
Schedule of Experiments table shows what experiments will be performed this
semester. It is labeled tentative
because availability of reagents and instruments and other unexpected events
may force changes in what we will do this semester. Any changes will be announced in lab and on
the course web page. If an experiment is
deleted, then there will be an appropriate change in the point totals. The Experiment column indicates what number
will be associated with a given experiment for announcements, handouts,
procedural changes, and report forms (described later). The Title column gives three pieces of
information. It gives the title of the
experiment in the lab manual or a handout, the type of experiment as far as how
the notebook records will be kept, and how many points the report for the
experiment will be worth. The reference
shows where the procedure for a given experiment can be found. Most of the information that you need about
techniques and analyses for the experiments will be provided in lab lecture and
the notes provided on the course web page. However, if you feel that you are
having a hard time following what’s going on, you can try reading the technique
sections listed in this column. These
sections at the end of the lab manual sometimes provide more information than
you will need for the course however. In
some cases, a report form will contain questions that can only be answered by
reading these sections. I will try to
let you know about this in the report forms.
“Make Up Labs”
As
explained later, many aspects of the course are designed to represent how you
would actually function in a lab setting.
Obviously for the purposes of the course and safety, this won’t be
entirely true. In many ways, it will reflect
what is expected in academic, government, and industrial labs more so than your
previous courses. In most situations, if
an experiment fails because you make a mistake, you repeat it until it works or
a deadline passes. In past years we have
followed this policy. Sometimes this
required that a student come to another lab section to repeat and complete an
experiment. This was possible because
most lab sections were not full and there was always extra room. In the past 2 years we have had enrollment
increases that have led to sections remaining full for the entire
semester. If an experiment does not work
out for you or you miss a lab period, and it appears you can’t catch up, the
instructor will make a decision as to whether you can do an alternative
assignment on your own time. This semester we may often have you finish
an experiment in another lab section since the labs aren’t quite as full. The alternative assignment will involve using
IR and NMR spectra to determine the structure of organic compounds. They will be exactly the same in format as
the take home quiz in CHM 256. If you
miss the 40 point experiment, you will need to do 2 of these assignments. This can be only used to replace 1 lab. If other experiments fail, and you can’t
catch up in your normal lab period, you will just lose the points for that
report. Note that often there are
questions to be answered for reports so it won’t necessarily be the case that
you will receive a zero for a report.
These make up assignments will become available after spring break.
Experiment Procedures
Unlike what many of you may have experienced in other
lab courses, everything you need to know to conduct an experiment will not
appear in a single procedure reference. There are several reasons why this will
be the case. In this course you will be
using lab techniques that will be used for more than 1 experiment. For example, the technique known as simple
distillation is used in several experiments during the year. A specific explanation of how to set up and
perform simple distillations will not be provided in each experiment. The general method of performing this
technique along with safety precautions, theory, and other practical
considerations will be provided in the lab lecture and outlined in the notes
provided over the internet. Then in
specific experiments, it will be merely stated that you should perform a simple
distillation at given point in the procedure.
Perhaps modifications to the general method will be required as stated
in the specific procedure. Throughout
both semesters, you will be expected to modify and apply general techniques to
specific situations. You may never do
organic chemistry again, but you will be expected to modify general procedures
to specific circumstances for the rest of your careers. Due to changes in the availability of
reagents and instruments or for other possible reasons, there may be changes
made to Handout and lab manual experimental procedures. These changes will be posted in the Handout
link of the CHM 258 course website. You
will need to adapt the Handout or lab manual procedure according to whatever is
listed in the corresponding links. For
e.g., in Experiment 3A, you will need to check the Handout link to see whether
there is another link entitled “Changes to Experiment 3A”. Making adjustments to procedures such as
these will also be something you will be doing the rest of your careers. To sum up, to conduct an experiment you may
need to consult the reference, your lab notes, and a link for specific changes. You will then need to decide how to put all
that together to complete an experiment.
You will not be able to conduct
your experiments with the lab manual or handouts in front of you. Instead, you will need to write an outline of
the procedure for an experiment . It
should be as detailed as you think necessary so that you can conduct the
experiment. That is what you will be
allowed to use. You will not need to
turn them in, but I will need to check that you have written them. This semester, we are going to start the 1st
experiment on the 1st day.
This will be the only exception to preparing an outline. I apologize that this has become necessary
this year, but too many students came unprepared for lab and consequently took
too long to complete experiments last year.
Part of what you will learn
in this course is how to read a procedure.
Not every procedure you read in your career will be as clear and
complete as you like. The same is true
in this course. Some of the procedures
in the lab manual are very good and some based on student comments leave
something to be desired. The best way to
learn how to read procedures is by attempting to do them and asking
questions about whatever seems to be unclear.
Grading
Reports
Each lab report will be
worth the amount indicated in the Tentative Schedule of Experiments. The format will vary with the
experiment. The format, due dates, and
some indication of how the reports will be graded will be provided on the CHM
258 home page. Each instructor has red
and yellow bins beneath the instructors’ bench. Be sure to place all reports in
the red bins on the day they are due.
The instructor will note at the end of the lab period whether they are
there or not. Sometimes, you will turn
in samples that you prepared or isolated along with your reports, they should
always go in the yellow bin the same day that the corresponding report is due.
If you don’t place samples and reports in the correct bin, then they won’t be
considered turned in for grading. This will
insure that your reports and samples don’t end up with the wrong instructor or
being ignored because they ended up some place unexpected. Grading in the reports will be based more or
less on the results of the experiment.
Spectra and chromatograms can be stapled to the report. Also, products
of reactions will be turned in with the report.
Each person will be allowed up to 2 late reports. Once the limit is reached, the following
policy will apply. 5% of a particular
lab report grade will be deducted if it is not turned in on time. If the lab is more than 1 week late, 50% will
be deducted. If the lab is more than 2
weeks late, no credit will be given. However,
under no circumstance will a report be accepted if graded reports for that
experiment have already been returned to the class. The total number of late reports at a given
time will be announced. No reports will
be accepted after May 3 in Dr. Maloney’s sections. Dr. Tahmassebi will give final deadlines for
their sections. These deadlines reflect the fact we must turn in grades by 5:00
PM May 8. Once that deadline has passed, grades won’t be changed. Of course it should be assumed that items
such as your name and complete titles for tables and plots should appear in
your report without being specifically instructed. Extraneous marks and smudges should not
appear on data (spectra, chromatograms).
The reports must be typed. In
many cases you will be asked to answer questions or write a short paper on a
specific topic. We don’t mind and actually encourage you to work together. In fact you may ask your instructor questions
to insure that you receive the highest possible score. However, we do expect that you write answers
and short essays in your own words to the best of your ability. Points will be deducted in reports for
answers that have the exact same wording.
In the end, the point is to learn how to conduct experiments in organic
chemistry. If you can learn from each
other, that’s great. However, quickly copying an answer is not learning.
The notebooks and
reports from Dr. Maloney’s lab sections last semester are available in the prep
room. They are sorted in alphabetical
order and lab section. Please pick up the
reports so that you can improve on your reports this semester. In particular, you will be asked to write
more procedures in the American Chemical Society format. Please look at your acetanilide and isopentyl
acetate reports. You will notice that I made
numerous corrections. In those cases
where I thought you should have been able to correctly include information
based on the examples, I took off points.
However, this style of procedure is often quite new to students so I
didn’t take off points in other cases but I make extensive annotations of
changes. Please check these so that you
can make changes for reports this semester.
Technique
You will be graded on
your safety practices and the skill with which you perform experiments. This
technique grade will be assigned at the end of the semester. Normally, we will take the total grade of
your reports, divide that by the total possible report grade and multiply by
40. Your technique grade would then
reflect how well you performed the lab and knew the material. However, we reserve the right to deduct
points from this value for the following reasons.
·
Safety practices as described in the safety sheets, notes, and lab
manual are not followed. This
particularly includes not wearing goggles.
·
Waste is not placed in the appropriate bottles. Acetone should never be
disposed of into a sink. There is an
acetone waste bottle.
·
The instruments have not been treated with care.
·
Suggestions by the instructor for an
experimental procedure or apparatus set-up are not followed.
·
Student samples stored in the
refrigerator or drawer are not properly labeled. (This includes the NFP numbers when
available. These will be explained in
the course notes.)
·
The caps of reagent bottles have not
been replaced after use.
·
Reagents and solvents have been
contaminated. This can be avoided by not
replacing unused reagent or solvent to their original containers. Place unused material in the waste
bottles. Also, you should not directly
pipette reagents and solvents from bottles.
Pipettes that have not been cleaned and dried have been a cause of
contamination previously. Pour liquids into a beaker or flask and then use the
pipette. Then if your pipette is dirty,
it affects only your experiment and not others. This requires that you minimize
how much material is poured out so that we don’t waste expensive chemicals and
don’t unnecessarily add to the waste that must be disposed.
·
Magnetic stirrers, digital
thermometers, hotplates, water faucets, gas lines, m.p. and air lines have not
been shut off. Hood sashes have not been
closed. The m.p. apparatus and balances
should be turned off at the end of the lab period if you are the last to use
them.
·
Reagents and equipment are not
properly replaced to their shelf or drawer location. In particular, the acetone and distilled
water bottles should be returned to the appropriate shelf.
·
A student has a higher than usual rate
of equipment breakage.
·
If water is to be used for your
experiment other than a hot or cold water bath, always use the deionized water
from the gray faucets. After cleaning glassware
and equipment with tap water, always rinse with deionized water. There are sufficient contaminants in tap
water used for lab to adversely affect experiments. Experiments have been chosen that generally
work well despite whatever mistakes are made, but it is always good technique
to use deionized water.
The number of points deducted will be determined by the instructor and
announced to the student. This policy is
not meant to be punitive but to help you become competent in lab. Although you will see some of these
techniques in later lab courses, CHM 254 and CHM 258 are essentially designed
to be the only courses where you will learn to function in a lab that does
organic chemistry. Even some
non-chemists are expected to perform the techniques covered in these courses
occasionally. If you don’t learn it
here, you won’t impress your coworkers, professors, and bosses by learning it
on the job later.
Notebook
You will be required
to keep a laboratory notebook using the following guidelines. Although it will not be entirely true for the
purposes of the course and grading, the following guidelines represent how
notebooks are to be kept in various lab settings. Some of the more fussy guidelines actually
are present for legal reasons.
1.
A bound notebook must be used.
2.
A table of contents must be placed at the beginning of the notebook. For each experiment entry, give the title,
the start date, and the page number.
3. Number the pages of the notebook if
necessary.
4.
Use only pen in recording entries.
5.
When making corrections, place a single line through the error. e.g. Then 10
ml 8 ml of ethanol was ...
6.
Mark the date of each new notebook entry.
7. Sign each notebook page.
8. Have your instructor sign each notebook page
at the end of the lab period.
9. For each reagent or solvent that you use,
indicate in parentheses whether it was prepared by the stockroom or was
provided by a specific vendor e.g. Aldrich, Fischer, etc.)
10. If possible, avoid leaving blank pages. If you leave a blank section on a page or do
have a completely blank page, place a large X though it.
11. Two types of experiments will be performed throughout the course. Either you will synthesize and isolate a compound (synthesis experiment) or you will perform a specific laboratory technique or analytical test. (analytical/technique experiments). The notebook entries for each type of experiment will be somewhat different. For analytical/technique experiments use the following format:
12. If you must continue an experiment entry on nonconsecutive pages, then place the title of the experiment at the top of the page. Also place the phrases continued on p. # and continued from page # at appropriate locations.
Analytical/Technique
Notebook Entries
a. Place the title of the experiment at the top of the page.
b. Write the
reference for the procedure. (See last two pages for preferred style.)
c. Write out a
table containing the names of the compounds used, pertinent known
analytical data such as m.p., b.p. etc. (obtained from the CRC Handbook of Chemistry and Physics, Merck Index, or Chemfinder.com) and any particular hazards presented by the compound. Under hazards, indicate whether the compound is known to be toxic, flammable, explosive, an irritant, etc. (obtained from the Sigma Aldrich Library of Chemical Safety, the Merck Index, or Chemfinder). This information may appear on the bottle's label. Occasionally, the instructor or notes will inform which compounds should be included in this table. If this information is not provided, then you must decide what to include. You may of course ask your instructor if you’re uncertain.
d. (Optional) If you wish you may write a short introduction about what the goal of the experiment is. You may also write your outline in the notebook. These two are entirely up to you. If you do include these, I may only skim through these and not grade them.
e. Write the procedure you used to perform the experiment in full
English sentences. Avoid the use of the pronouns I, we, and they. Place the
date on which that portion of the procedure was performed on the left-hand side
at the beginning of the narrative. Be concise, but include enough information
so that anyone can read your notebook and do the experiment.
f. Be sure to include all observations (e.g. color changes) and all
data collected (masses, m.p., b.p., etc.)
A copy of chromatograms and any spectra obtained should also be placed
in the data section.
Synthesis
Experiment
a. Place the title of the experiment at the top of the page.
b. Write out the reaction(s) performed directly below the title.
c. Write the reference of the procedure. (See last two pages for
preferred style.)
d. Write out a table containing the names of the compound used, their
molecular weights, the amount of each compound used, the number moles of each
reagent (actually appears in chemical equation for experiment) used and
pertinent analytical data known about the compound and its known hazards. For
the product of the reaction, write the theoretical yield in grams and moles on
the table. Upon completion of the experiment, write the actual yield and
percent yield below them.
e. Include an introduction and
outline if you wish.
e. Write the
procedure section in the manner described above.
f. Include the data in the manner described previously. Be sure to include copies (reduced in size is
convenient) of IR spectra, GC-MS data, and NMR spectra if necessary for the
experiment. We’ll learn what the terms
IR, GC-MS, and NMR mean later.
At the moment, I plan
to check the notebooks every few weeks. The total notebook grade will be 65
points at the end of the semester. Dr.
Tahmassebi may have a somewhat different procedure. In general, notebooks are not meant to be
works of great literature. However,
organic chemistry notebooks are meant to allow anyone to successfully repeat an
experiment. The procedure section (and
handwriting) should be clear enough that any person with a sufficient
background in organic chemistry could read it and perform the experiment. As a result I will not always correct grammar
or spelling. However, if a misspelling
or poor grammar could result in someone making an error, then points will be
deducted. Also, if an error would make
you look particularly unprofessional if made in an industrial or research lab
setting, then points will be deducted.
Organic chemistry notebooks tend to be longer and more detailed than any
notebook you may have kept in the past or in the future. This is because the procedures described are
often unique to that particular experiment and must be explained. Many of these procedures are not common
knowledge even to practicing organic chemists.
Some procedures are common and done more less the same over and over
again. When this is the case, it is only necessary to state that the procedure
was done and not give details. For
example, you have learned how to take melting points. This procedure is more or
less the same every time. It will be
sufficient to say, “A melting point of the sample was obtained.” Note, sometimes, the same information will
appear more than once in a given notebook entry. For example, % yield will appear in the table
in the beginning of the experiment and in the procedure.
Examples of notebook
entries are provided at the end of the syllabus.
Quizzes
Announced quizzes (10
to 30 pt. each) will be given. They will
cover practical aspects of organic chemistry, some theory, and aspects of the
experiments you are performing. (It has
already been asked. No you may not work
together on quizzes and the final like you may for the lab report
questions.) There will be a
question on calculating limiting reagent, theoretical yield, and % yield on
each quiz.
Some Further Comments About Grading
If an error is
corrected and no points are lost, this means that you should avoid this error
in the future. If the same error is made
later, points may be lost.
Although you may help
each other, each student (or pair of students where appropriate) is expected to
provide their own data and samples for each lab report. Each student is expected to provide a
separate and unique lab report unless you are working as a pair as designated
for a given experiment. In the recent years, there have been 4 cases of
cheating on lab reports among the organic lab courses. In two cases, they involved the unauthorized
use of another student’s data. The other two cases involved copying entire
reports. You may not consider this
unethical, but it will be considered that way in this course. I and the other instructors reserve the right
to take 1 of the three following actions:
·
You will receive 0 points for a given
section of the report.
·
You will receive 0 points for the
entire report.
·
You will receive an F for the course.
Due to the fact that I am busy and usually err on the side of a
student, I am sure that I have missed some cheating through the years. However you can assume that I and the other
instructors may notice spectacularly obvious examples like those 4 noted. The cases of unauthorized use of data
involved output from the instruments used during the semester. You should realize that each instrument’s
output consists of a certain amount of irreproducible electronic noise. The probability that the same instrument will
give the same exact results twice is negligible.
Course Announcements
Announcements for the
course will be given in lab and on the CHM 254 home page. Please read them since none of the lab
instructors will want to repeat them over and over because students have not
read them.
Lab Lectures and Course Notes
Lectures explaining
the experiments, practical considerations in organic chemistry, and some theory
will be given on many but not all lab periods.
The notes will be presented on transparencies. You have been provided with the notes for the
first two lab lectures. Due to our
different teaching styles, Dr. Ericson and Dr. Tahmassebi may use different
notes. Students in those sections will
still have those from the web page available, it’s just that Dr. Ericson and
Dr. Tahmassebi may provide something different at their discretion. The remaining lectures for the semester must
be printed from the internet. See the
CHM 254 home page. Use the computers on
campus to print the notes if one of sufficient quality is not available to you
off campus.
Lab Computers
Two computers and one
printer will be available to you during lab (another one may become available
during the semester). One computer is in
the organic lab. The other computer and
the printer are located in the physical chemistry lab across the hall in room
SB 454. You can check course
announcements and notes. They can be
used to look up compound properties on www.chemfinder.com. Changes can be made to lab reports and
printed. Other uses for organic lab will
be announced at the appropriate time.
You may find it useful to save some of your data on a USB drive.
Lab Lockers, Hoods, and Benches
You will be assigned a
drawer and a hood for the semester. The
locker will be only yours, but the hood will be shared with other laboratory
sections. You will be expected to clean
your hood at the end of each lab period.
Your drawer will be expected to be clean at the end of the
semester. Clean it on a regular basis so
that it does not become stained.
The stockroom
personnel are very busy; please do not make extra work for them. Return all chemicals and equipment back to
their proper locations. Clean up after
yourselves. Although I avoided it until
last year, it will be necessary to assign groups of students to clean the lab
each week. On a rotating basis, 4
students will be asked to clean bench tops, shelves, balances, etc. at the end
of the lab period. The next week,
another 4 students will be assigned final clean up. We will attempt to make sure that all
students will perform cleaning an equal number of times. We can’t guarantee that this will work out
perfectly however. However, it is in
everyone’s interest to clean up after themselves so that when they are assigned
cleaning duty, they won’t have much work to do.
If you leave a mess for others, the day you are assigned could get
ugly. It will be left to the
instructor’s discretion to assign students who leave a mess more clean up
assignments than others.
Organic Chemistry Lab vs. General
Chemistry Lab
In several ways,
organic chemistry lab is much different than general chemistry lab. In certain
ways, organic chemistry lab reflects what it's actually like to work in a lab
more than general chemistry.
·
Most experiments will last more than
one lab period.
·
Often, you will be working on more
than experiment at once.
·
The experiments involve techniques
used by people who do organic chemistry part or all of the time: distillation,
recrystallization, reflux, IR, NMR etc.
·
Much of the equipment and many of the
instruments are exactly the type that would be used if somebody were doing this
for "real".
You will budget your time. You
can leave early and when there is no lab lecture, you can show up a little
late. You can take breaks if you
want. There are two limitations. The less you do in lab, the more that must be
done outside of lab. We can't or won't
necessarily stay late or show up early to accommodate your schedule. Although we have arrived early or stayed late
for students in the past, we may not have the flexibility in our work schedules
to do this as much this year. If
you don't get the experiment done by the due date because you did not spend all
the time in lab you could for it, then that's your problem. We realize that some students have difficult
schedules. For that reason, we are
trying to be as flexible as possible under current circumstances In the end however, you must complete the
same amount of work as everyone else.
Occasionally you may have to wait for a particular reaction to finish,
or you may complete a procedure early.
This is a good time to work on your notebook, reports, or other
experiments.
Sample Labels
To reflect more
stringent safety requirements imposed by various governmental agencies, you will
be required to label all samples that are to be stored in your drawer or
refrigerator. Using one of the labels
with the 4-color hazard diamond, write down the name of the compound, the date,
and your initials. Then when available,
write the hazard numbers in the appropriate boxes. Further explanation will be provided in lab
lecture.
Thermometers
Please always place
your thermometers with the bulb pointing downwards in the plastic tubes mounted
on the inside of your lockers.
Instrumentation and Instructor
Availability in Lab
One of the changes
that have occurred in the past 15 years in the teaching of organic chemistry
lab is the increased use of instrumentation.
Every chemist that does organic chemistry needs a working knowledge of
the instrumental techniques known as infrared spectroscopy (IR), mass
spectrometry (MS), and nuclear magnetic spectroscopy (NMR), along with some
others. You will use these instruments
often which will be good for your training.
The only drawback is that as students learn these techniques in lab, it
takes up much of our time in lab, and we often cannot answer student questions
immediately. We apologize if you must
wait. We are considering possible
solutions to this problem, but it has not been solved yet.
What You Should Know From General
Chemistry
You will be expected
to know the following from general chemistry lab. These topics will not be covered in lab
lecture this semester. Either read the
appropriate section in your lab manual if you have forgotten or ask questions.
·
How to calculate molecular weights
·
How to calculate limiting reagents
·
How to calculate theoretical yields
·
How to calculate % yields
·
How to use a balance and measure
masses
·
How to use graduated cylinders,
volumetric flasks, and volumetric pipettes
·
How to use Bunsen burners
What You Should Know From Last
Semester
·
Recrystallization
·
Gravity
filtration
·
Vacuum
filtration
·
Heating
under reflux
·
Simple
distillation
·
Fractional
distillation
·
Use of
drying agents
·
Preparation of
a liquid sample for IR and use of the FTIR
·
Extraction
·
TLC
·
GC
·
GC-MS
You May Have Seen This Experiment Before
There are some high
school chemistry teachers in the area that work very hard at trying to prepare
their students for college. They often check
what laboratory experiments are being used here and incorporate them in their
courses. Inevitably, some of you (but
not all) will be seeing some of the experiments for a second time. The experiments for this semester have been
specifically chosen because of what they teach about organic chemistry and
because they work reliably if performed properly. They are particularly useful for the people
that haven’t seen them yet. Unfortunately,
this will be the second time for some, but the practice won’t hurt.
Care Around Instruments
The lab and
instrumentation available for it are comparable to what most other students
have for organic chemistry lab at other schools nationally. Although some the instruments are getting
older and the computers in some cases are awaiting upgrades, they still provide
data that can be published in scientific journals and used for government
testing. The lab itself was built in
1998 and is only now starting to show wear.
I’ve been other places and believe me, many other organic labs look far
worse after 8 years. The reason we have
good instruments (if older) and facilities is partially due to the fact that
the faculty and staff have worked hard to obtain funding and maintain them. It is also due partially to all the previous
students who have been careful using them.
Scientific equipment and instrumentation is expensive, and it was
difficult enough as it was to obtain money from the National Science
Foundation. We can’t afford to replace
them due to people being careless. The
infrared spectrophotometer and gas chromatograph - mass spectrometer that you
will use originally cost $25000 and $70000 respectively. Even minor repairs are often not cheap. No one is going to give us money to repair or
replace them if they know we’re being careless.
For the sake of the quality and reputation of the education for
yourself, your friends, and all IPFW students present and future provided here,
please be careful with the instruments, equipment, and facilities so that they
may be available in the future.
For reasons related to
cost, safety, and hazardous waste disposal, we are using smaller amounts of
various compounds. Such small amounts
are difficult to measure accurately and precisely with the balances normally used
for organic lab. Recently we purchased a
Mettler Toledo analytical balance to handle these small amounts. It is located in the organic prep room
between the west door and hood. It cost
$3050 and we would like to make it last also.
Please be careful with it and use it only for the experiments indicated
in the announcements or notes. Also, do
not move the balance, it will affect the accuracy of measurements.
Occasionally, you will
use Teflon thermometer adaptors for some of the apparatuses you set up. These will be found in containers attached to
your hood. Please return them at the end
of the lab period. We have a limited
number and need them for all lab sections.
Safety Note
Although safety is
covered in the separate sheets provided and covered on the 1st day,
it should be pointed out that the most common and otherwise relatively
non-hazardous solvents used in organic chemistry have been linked to birth
defects when pregnant women were in contact with them. If you become pregnant during the semester,
we will try to find some way to accommodate you through either an incomplete,
withdrawal from the course, or special experiments. It depends on what point in the semester you
find out. In this case, I will err on
the side of safety and suggest that you no longer work with these
materials. Of course you should consult
your doctor.
Useful References
1. R. C. Weast, ed. "CRC Handbook of Chemistry and Physics",
70th ed. CRC Press,
2. S. Budavari, ed. "The Merck Index", 12th Ed. Rahway, NJ.:
Merck & Co., 1996
3. J. Nagarkatti,
4. R. E. Lenga, ed. "The Sigma-Aldrich Library of Chemical Safety
Data Edition I", Aldrich Chemical Co.
5. C. J. Pouchert, "Aldrich Library of Infrared Spectra", 3rd
Ed. Aldrich Chemical Co.
6.
ChemFinder Database and Internet
Searching, www.Chemfinder.com
7.
NIST Chemistry WebBook, http://webbook.nist.gov
The IPFW Organic Chemistry Resources Page also contains links to useful references. In particular, Material Safety Data sheets (MSD) can be obtained which may be helpful for entering hazards into the notebook.
