Help with lap report. Organic chemistry

Information for Written Lab Reports
The ability to write technical information in a way that is clear to others is an important skill for
any scientist. Like any other skill, you can only acquire this by practice.
Submission Requirements
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The full report (with all figures and structures) must always be turned in electronically via
Canvas.
All students must submit their own report, there are NO group reports.
The file name should contain the experiment and your name. However, the file name
should not be too long.
Academic Integrity
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Academic Integrity is expected of all students: https://provost.asu.edu/academicintegrity
Academic dishonesty will result in punishments varying from failing the assignment
along with a deduction of 50-100 points from your overall class score, failing the class,
failing the class with the score “XE” (failure due to academic dishonesty), or even
expulsion from the university: https://provost.asu.edu/academicintegrity/defined
Make sure to cite all references (internet, lab manual, journal articles, books, etc.). Only
credible sources should be used for the report such as books, journals or your own lab
packet. Wikipedia, About.com, ehow.com, buzzle.com, etc. are not considered
acceptable reference sources.
It is allowed to directly quote a small portion of a reference, as long as you correctly use
quotation marks. However, large quoted sections will not be accepted and will result in a
loss of points.
If you obtained permission to use someone else’s data (e.g., because you were sick or
the experiment failed), then clearly indicate the source in your report.
Your submission will be checked using “Turnitin” for plagiarism, where you copied from
other sources and did not cite them, and also for SELF-PLAGIARISM, where you copy
and paste something that you wrote previously (please see the next section for more
details).
Plagiarism and Self-Plagiarism
Plagiarism is defined as “the practice of taking someone else’s work or ideas and passing them
off as one’s own”.
Self-plagiarism is defined as “the use of one’s own previous work in another context without
citing that it was used previously”.
Examples of plagiarism and self-plagiarism that are relevant to your organic chemistry lab
course are:
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You copy and paste sections of text into a lab report that was taken from the provided
course materials, from a book or from any other printed or online source, or from a lab
report from a current or a past student.
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You copy and paste a reaction equation, mechanism or experimental apparatus from the
provided course materials, a book, any other printed or online source, or a report from a
current or past student.
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You work together with another student on an assignment or project using an application
with file sharing feature like Google Doc, and you and the other student submit a
document that has some of the text that has identical wording.
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You try to help another student by giving or showing them your assignment or project as
an example, and the individual copies or modifies what you wrote and submits this
material as part of their own assignment.
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You try to help another student by editing that student’s work. As the result, you and the
other student end with some text that has the same wording.
Note: Even though a student and their lab partner have the same lab data, copying and pasting
of results, equations, and images, calculations, or data in a table is considered plagiarism.
It is important to understand that both plagiarism and self-plagiarism can be accidental. Even if
accidental, they are still plagiarism and self-plagiarism.
Some Ways to Avoid Plagiarism
Plagiarism can easily occur if you share a completed assignment with a classmate in an
innocent way to help them answer a small question about format or data or style. Because your
report is now available to your classmate, it is too easy for them to cheat by copying even a
small part of work with or without your knowledge. How can you avoid this? When working on
an assignment with a classmate you should take notes when together, and then complete the
assignment on your own at a later date using the notes.
Consequences of Plagiarism
If plagiarism is discovered, then both students receive zero points for the assignment. If a
student is involved in a second occurrence of plagiarism they will receive a failing grade for the
course with “XE”, which means “failure due to academic dishonesty”. Obviously it is impossible
for us to know who copied from who in a case of plagiarism, therefore, make sure that it doesn’t
happen to you by not sharing completed work with any of your classmates. You can work
together to generate notes that are used to complete the assignment, but complete all
assignments on your own!
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General Formatting
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Your report must be typed and double spaced (except for the abstract).
Each page must contain a page number.
Organic structures, equations and mechanisms can be drawn using computer software
or you can draw them by hand then photograph and paste them into your report. In
either case you images must be very clear, neat, legible, and straight and should not
have excessive white space around them. ONLY high quality images will receive
full credit. If you are unsure if your image is high quality speak to your TA before you
turn it in.
The file you will upload must be in pdf format.
Figures of non-chemical structures (e.g., apparatus diagrams) may be taken from
outside sources as long as the source is clearly cited.
All figures and structure must be properly labeled and described directly under the
figure.
Do NOT use “I” or “We” or any other types of pronouns.
Verb Tenses:
o When discussing information taken from the experiment after it is finished (e.g.,
Abstract, Procedure, Data/Calculations, and parts of Discussion) use the past
passive voice:
▪ The objective of the experiment was…
▪ The apparatus was placed…
o When discussing information that exists before, during, and after your experiment
(Introduction and parts of Discussion), you should use the present or future
tense:
▪ The purpose of this report is…
▪ Distillation theory states…
SEE THE FOLLOWING PAGES FOR GENERAL
GUIDANCE WITH EACH SECTION OF YOUR LAB
REPORT. Refer to your Canvas module for EXPERIMENTSPECIFIC guidance on your lab report.
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Lab Report Sections
Title (should be descriptive enough to understand what the
experiment is about)
Your full name
Your lab partner
Your TA
Day and time of your lab section
Lab room number
Date
Abstract: single-spaced, about a paragraph long and written in past passive tense
It should briefly summarize the purpose of the work reported, indicate the principal
findings and point out major conclusions.
• State what was done—State the learning objective or goal of the lab (1 sentence)
• Identify the methods used—A summary of the major parts of the experiment, i.e.,
mention the techniques/methods used (1-2 sentences)
• Report the results—A summary of the major results from the experiment, i.e.,
what did your measure or do? Use actual values (2 sentence maximum)
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Introduction: Written in present or future tense, it should be double spaced and
include at least three paragraphs, but no longer than 2 pages with the following
information
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A summary of the overall objective of the lab, i.e., what are you trying to accomplish
by performing the experiment? If there is a chemical reaction, it should be mentioned.
o Provide essential background information for the reader to understand the
experiment
o A summary of how the experiment works and the theoretical
principles/background information for how the experiment or technique works
(very general).
o If techniques are included that you have not used before, then these must be
described and explained. Include synthetic, purification, and characterization
techniques. Figures and diagrams can be helpful.
o a summary of what you expect the outcome to be, what you expect to
observe and what you expect to learn by making these measurements.
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Experimental: Tell the reader what was done (written in past passive tense), in about 1
double spaced page. Remember you are writing to a chemist so don’t write unnecessary
details
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Describe the procedure YOU performed
This section should be detailed enough so that anyone could repeat the experiment,
but it should NOT be just a repeat of the details procedure given in the lab packet. Be
CONCISE!
o Example DON’T: “The experiment used roughly 150 mg of X and the exact
weight measured was 145 mg.”
o Example DO: “In this experiment, 145 mg of X was added to…”
See the example reports on Canvas to see how Experimental sections are written.
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Results: written in past passive tense This section should be 1 page maximum (excluding
tables/spectra, etc.). In general this section should contain all data related to all parts of the
experiments you performed. Anything recorded in your lab notebook goes in this section.
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Make tables to summarize your data including names, masses, and molecular
weights of the reactant and product
o Melting Points (experimental and literature)
o Extraction data
Show all your calculations specific to your experiment. For example:
o Moles of the reactant(s)
o Indication of limiting reactant (if any)
o Theoretical yield
o Moles of crude product
o Moles of pure product
o Percent yields of crude and/or pure product
o Percent recovery of recrystallization
Include the IR spectrum about the product (if you have one)
o On the IR spectrum, draw the structure of the final product
o Label the major IR peaks above 1500 cm-1
Include the Table of Frequencies and Assignments for peaks of the IR spectrum
Be sure to include captions for each Table, Figure, and Equation
The figures, diagram, and spectra should be clear and legible
• Data can relate to the observations that you made.
• This section summarizes the DATA ONLY, it does not include a discussion of what the
data means
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Discussion: written in past passive or present verb tense, depending on the topic. This
is generally the longest section of any lab report (2 pages max, EXCLUDING
equations/mechanisms, etc). This section should contain a discussion of the results and the
experiment. Here is where you describe what you did, what you learned, and explain how
you analyzed the data and observations and how you arrived at any conclusions.
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Restate the purpose of the experiment—Give the overall objective
o If you are performing a reaction, show the equations and briefly discuss the
reaction.
o If you are performing a reaction, give the MECHANISM and briefly discuss.
Discuss how the experiment was performed—why you did what you did, apply the
background information from the introduction to the experiment using specifics
about the experiment and discuss if the experiment turned out as planned in
relationship to all methods. Also discuss and changes to the plan.
Discuss specific results—Restate the results (melting point, IR peaks, Rf values,
percent yield, etc.) and interpret them. Do this for EACH result. Explain how the data
was analyzed and what conclusions were drawn and why. Support your conclusions
with theory!
Discuss sources of error—stating mechanical errors or human errors is not enough,
discuss where you could have gone wrong or where you actually did go wrong!
Summarize the work—A final summary of what you learned from the experiment—
was the experiment successful?
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Conclusion: written in past passive tense the conclusion should be one paragraph, about
5-7 sentences long.
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A brief summary of the purpose of the experiment.
A brief summary of the major parts of the experiment, i.e., very briefly summarize
what you did. This should only be 2-3 sentences maximum, no detail, the details
were provided in earlier sections.
Briefly restate the results—give specific values (melting point, percent yield, etc.).
A summary of what you learned from the experiment—was the experiment
successful?
References:
Include ALL references. You can use ACS or APA styles, just keep it consistent for all the
references.
The lab packet can be cited as follows:
Arizona State University (2018, Month and Day of retrieval). Name of the Lab Packet.
Retrieved from http://myasucouses.asu.edu
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Acetaminophen Lab Report
See the Lab Report Template for guidelines on formatting your Lab Report. Refer
to the information in this document for SPECIFIC topics to cover for this
experiment.
– Title
– Abstract
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Summary of the experiment (no experimental details such as masses, temperature, etc.)
Objectives of the experiment (which technique was used and why)
Results (% yield, melting points)
– Introduction (information from the gapped notes)
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Brief overview/introduction to synthesis and the reactions
Describe the reactions
Draw the equations for the formation of the acetaminophen
Brief overview of isolation/purification techniques and their uses
– Experimental section
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Write the procedure YOU performed
See the example lab reports on Canvas for examples of how the experimental section is written
– Results
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Yield (both % yield and % recovery)
Calculations including mass values of reactants/products, equations/units
Melting point range and labeled IR spectrum and table of frequencies
– Discussion (all discussion needs to be supported by theory, you will always be talking about your
specific experiment, with your own data and chemicals, but the explanation for it is based on theory)
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Purpose of the experiment again
Discussion of the reaction (why reflux, which bonds are made and broken, etc.)
Discussion of the theory for the purification techniques used, specifically for your own
experiment (IMFs involved, % recovery, etc.)
Discussion of techniques used for characterization yield and purity (by IR and MP), drawing
conclusions from the data about the success of the experiment
Discussion of what YOU learned/observed and possible reasons for lower yield (if at all)
NOTE: If your experiment failed, it is preferred you talk about that, instead of getting somebody else’s
data. YOU WILL NOT GET POINTS DEDUCTED FOR BAD DATA, BUT YOU WILL LOSE POINTS FOR NOT
PROPER USE OR LACK OF THEORY. We want you to discuss and analyze your data, even if it is not what
you expected. The only exception is if you got absolutely no yield, then you will obtain data from your
TA so that you can complete the results section. However, your discussion section should still include
why you experiment failed, etc.
– Conclusion
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Summarize the experiment
Objective of the experiment with the results (MP, IR peaks, and % yield)
– References
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Include more than one reference
Cite the lab packet:
Arizona State University (2018, Month and Day of retrieval). Name of the Lab Packet.
Retrieved from http://myasucouses.asu.edu
ALL FIGURES, DIAGRAMS, AND SPECTRA SHOULD BE CLEAR AND EASY TO READ. ALL CALCULATION
EQUATIONS MUST BE CREATED BY YOU. See the Lab Report Template for information how to create
your own equations.
Copyright, Arizona State University
Arizona State University: Organic Chemistry Lab Experiment
Making Chemicals!
Acetaminophen Synthesis Package
1. Background
• Chemical synthesis of new and functional chemical structures is one of the most important things that organic
chemists do.
• Chemical synthesis brings together many of the techniques you have learned so far.
• Synthesis starts with simple and readily available starting structures, and then via a series of bond breaking and bond
forming chemical reactions, converts and builds these simple starting materials into new and more complex structures.
• You will do this, although at a rather simple level!
• Examples of complex molecules that have been synthesized in the laboratory are shown below…
taxol
brevitoxin B
vitamin B12
ionomycin A
• Most syntheses require a series of chemical reactions to gradually transform and build upon simple starting materials.
The synthesis of vitamin B12 (above) took around ninety consecutive chemical reactions (90 “steps”) and took around
100 scientists around 11 years to accomplish!
• The synthesis you will do in this lab will be a lot simpler than that, you will only do one reaction!
1.1 A Complete Synthesis Generally Has Multiple Tasks
• There is no single procedure for performing a synthesis, different syntheses require different techniques, but your
simple syntheses will generally consist of the following tasks
perform
the
reaction
isolate
the
product
purify
the
product
characterize
the
product
This synthesis will combine many of the techniques you have learned so far this semester, including
recrystallization, melting point and infrared spectroscopy
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• This synthesis will also introduce a new concept: chemical reactions, heating (reflux) and thermal energy
• There is a lot to do this week, you will need to work quickly and efficiently
1.2 Performing chemical reactions: Why (Thermal Energy, RT) Matters
• A chemical reaction in organic chemistry requires the breaking and making of covalent bonds to convert one
chemical structure into another one
• Specific bonds need to be made and broken, how do we do that? There is no simple answer to this question; this
topic is the main subject of the year-long lecture course.
• The way that organic reactions occur at the electron level is not the focus of the lab course, here we focus on the
practical aspects OF running reactions
• But we do need to discuss one theoretical aspect of organic reactions that does relate to lab technique, i.e., the
order in which bonds are made and broken…..
The Organic Reaction You will do in This Lab:
Some Definitions:
The organic molecule that is transformed (via breaking and making bonds) in the reaction – The Reactant
The organic molecule that is formed in the reaction from the reactant – The Product
Other chemical(s) that we need in order to break and make the bonds in the reactant – The Reagent(s)
Other products of the reaction that are necessarily formed in the reaction, often derived from the reagents – The
byproduct(s)
Other chemicals formed that are not formed in the desired reaction, but a different undesired reaction: SideProducts
• NOTE in the inclusion of the term “heat” in the equation, this is the part of the reaction conditions that is important
for the reaction
• Exactly how this reaction proceeds, i.e. the detailed mechanism (and also the naming conventions for the various
chemicals) are the main subject of the lecture course, and we don’t expect you to understand these details yet, and
you don’t need to know these details to perform this lab. However, you should be able to recognize which bonds
are broken and made and what general things are involved in your lab synthesis and why you do what you do that
enables the bond making and breaking processes to occur.
• Bond breaking must happen in the first steps for almost all organic reactions because you can’t make a new
bond to an atom until you have broken one of the bonds that are already there
• Breaking bonds requires energy since the energy of the electrons are higher when they are not in a bond. This is
why almost all organic chemical reactions have an activation energy, i.e. an energy barrier that must be
overcome.
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Energy
required energy = Ea
activation
energy
Ea
energy
barrier to
reaction
Ea
k = A e – RT
reactant
available THERMAL energy = (RT)
exothermic
product
Reaction Progress
• Your reaction is more complex than indicated by the diagram above, but it makes the point that we must add
energy, even if the overall reaction releases energy (it is exothermic)
• The required energy is the Ea
• The available thermal energy is given by (RT)
• This is the reason for the “heat” term in the reaction conditions
1.3 Controlled Heating of a Reaction: Reflux
• There is also no single procedure for heating a chemical reaction.
• One method that is often used that gives temperature control is reflux
• Reflux means boiling the solvent that the reaction is being performed in, but CAPTURING the evaporated solvent by
condensing it and causing it to return BACK into the reaction vessel:

• The temperature of the reaction will be the temperature at which the solvent boils
• Here are some different ways of getting heat (RT) into a reaction to make it go faster
1.4 Isolation and Purification of the Crude Product
• At the end of the reaction you will have to separate the product molecules you want from all the other stuff in the
reaction mixture, this is called isolating the product.
• In this experiment you will isolate the product by helping it to form crystals, by lowering the temperature. The idea
is that only your product will form solid crystals that you can then isolate via filtration:
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• Isolation consists of two steps, crystallization followed by filtration to form the Crude product
• After isolating the crude product you will need to purify it, which you will do via recrystallization in a test tube.
recrystallize in a test tube
ice bath
• After recrystallization you will have the purified product
1.5 Identification of the Product
• After you have isolated and purified the product you will characterize the product using melting point and IR
spectroscopy
• You will use the correlation chart, shown below, to identify the peaks in an infrared spectrum that are associated with
vibrations of specific bonds that are associated with specific functional groups in the product of your reaction
• The product of your reaction has an amide functional group, you should expect to see two vibrations in an IR
spectrum for this functional group
• There should also be vibrations corresponding to the alcohol functional group, the aromatic ring and C-H bonds
• IR spectroscopy can be used to characterize structures in organic chemistry
1.5 How Much Reagent? Limiting Reactant/Reagent
• Organic equations can be deceiving, it looks as if we are saying that 1 molecule of the reactant reacts with 1
molecule of the reagent to give 1 molecule of the product and 1 molecule of the by-product, and in fact we make it
worse by saying stuff like this in recitation and in lecture. But that isn’t it, is it?
H
N
H
H
+
H 3C
O
O
C
C
O
O
N
CH3
O
trillions of molecules
O
H3C
H
O
trillions
trillions
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H +
H
C
O
CH3
trillions
• There are actually trillions of molecules of the reactant, and trillions of molecules of the reagent etc.
• Usually we don’t even try to have an equal number of molecules of reactant and reagent (imagine trying to count
trillions of molecules and then trying to match to trillions of molecules of the other)
• Usually, one of these is in excess (more molecules than the other one), usually the reagent
For Example:
First: determine the number of moles of the reactant and the number of moles of the reagent for your reaction
(shown below), not molecules (numbers of molecules are too large and unwieldy)
Second: if the number of moles of one is larger than the other then that one is in excess and the other is the
limiting reagent
Note: We must compare the number of moles, we can’t just compare the weights of the reactant and the reagent,
because each molecule has a different molecular weight!
Calculating Numbers of Moles:
• You have already done this, but let’s make sure you are doing it correctly…..
weight (g)
(assume that mass ~ weight)
# of moles =
molecular weight (g/mol)
H
N
H
H
+
H 3C
O
O
C
C
O
O
N
CH3
O
p-aminophenol
H
acetic anhydride
weight = 887 mg
weight = 345 mg
mol. weight = 102.1 g/mol
mol. weight = 109.1 g/mol
# moles = 0.00869
# moles = 0.00316
LIMITING
REAGENT
O
H3C
MORE moles
H +
H
C
O
CH3
O
0.00316 moles
MAXIMUM
0.00316 moles
MAXIMUM
EXCESS
• There are fewer moles of the p-aminophenol than there are of acetic anhydride
• p-Aminophenol thus limiting, there can only be as many moles of the product formed as there are moles of the the
limiting p-aminophenol
Why Use an Excess of one of the Reagents
1) As reactions proceed the concentrations of the reactant and reagent decrease, this makes the reaction go slower,
having an excess of the reagent reduces the tendency of the reaction to go slow at the end because its
concentration is always high
2) Having excess reagent tends to ensure that all of the reactant actually reacts (you don’t “run out” of reagent)
3) Reagents, as opposed to the organic reactants, tend to be inexpensive!
1.6 Calculating the Product Yield in your synthesis
• It is always important to determine how efficient your synthesis is, in other words, does your synthesis produce the
maximum number of molecules that it can?
• How can the maximum number of molecules not be formed? Several possible reasons:
1. Incomplete Reaction. Sometimes the reaction does not go to completion, some of the reactant remains unreacted
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2. Formation of Side-Products. Some of the reactant can sometimes undergo an unwanted side-reaction, in addition
to the desired reaction, not all of the reactant makes the desired product
3. Mechanical Losses and/or Errors. This covers a lot of possibilities, for example, some of
the product is lost when recrystallizing, or weighing, or drying or transferring, or you make an
error in your experiment, you weigh an incorrect quantity of chemical……
……… or sometimes you just spill everything on the floor!
• The maximum number of moles of the product that can form is equal to the number of moles of
the limiting reagent the reactant, this is the theoretical yield
• The chemical yield is the ratio of the actual number of molecules (moles) of the product you make, to the theoretical
yield, or molecules, the reaction should produce
2. What You Will Do
2.1 Synthesis of acetaminophen
2.1.1 Perform the Reaction
Note: Make sure that the micropipettes are set to the correct volume before you sue them, and, make sure that you
always use a clean pipette tip! If you are unsure about how to use the micropipettes, ask your TA!
• Weigh roughly 150 mg of p-aminophenol into a 5 mL conical reaction vial. Record your exact weight
Perform the next steps in a hood
• Add 0.5 mL of water then 0.3 mL acetic anhydride to the vial. Do not add too much acetic anhydride!
• Place a magnetic spin vane in the vial and attach an air condenser.
• Heat the reaction mixture in an aluminum block until gentle reflux and stir gently using the magnetic stirrer.
• After the solids have dissolved, continue to reflux the reaction mixture for another 20 mins. Control the heat input
from the heating plate so that you see reflux of the water solvent in the lower end of the air condenser.
VIDEO HELP…….
To assemble the apparatus: https://www.youtube.com/watch?v=yOe4ScCnBAM (you will not use a drying tube)
Using an air condenser: https://www.youtube.com/watch?v=V01klyOvCyI
Reflux (but not with a microscale apparatus): https://www.youtube.com/watch?v=3diTdagF-6U
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REFLUX
~150 mg
p-aminophenol
0.5 ml
water
air condensor
condenses
spin
vane
solvent boils
solvent returns
plastic cap
stir bar
0.3 ml
acetic
anhydride
aluminum
block
2.1.2 Isolate the Product
• Remove the vial from the heat and allow it to cool. After it has cooled, remove the air condenser and the spin vane
using forceps.
• Rinse the spin vane with 2 or 3 drops of water into the reaction vial.
• After the solution has cooled you should see crystals start to form.
• If no crystals form, scratch the inside of the conical vial below the surface of the liquid with a clean glass rod.
• Cool the solution further by placing the vial in an ice bath.
• When the solution is cooling in the ice bath, setup a Hirsch funnel for filtration.
• Remove the solution form the ice bath and as quickly as you can (i.e. before the solution starts to warm up again),
filter in order to isolate the crystals of the product.
• Rinse the vial with roughly 0.5 mL of COLD water and use this water to wash the crystals on the funnel.
• Dry the crystals by allowing air to be drawn through them on the filter paper for 10 – 15 minutes.
• Weigh the solid crystals and then crush them to make the next recrystallization step easier
•Take a small quantity of the crushed crystals and put into a melting point capillary for melting point analysis.
air
2-3
drops
water
wash 0.5 mL
COLD H2O
rinse
spin
vane
dry
Hirsch
funnel
vacuum
COOL!
weigh!
vacuum
ice bath cool AFTER
crystals form
2.1.3 Purify the Product
• Purify the crude reaction product by recrystallization in a small test tube.
• Put the crude product into a test tube and put the test tube in a small beaker with water on the hotplate. Add
hot 50:50 methanol:water that is contained in a separate beaker that has also been warmed on the hotplate.
• In the test tube, dissolve the crude reaction product in the minimum volume of the 50:50 mixture of HOT
methanol and water. The methanol/water mixtures will boil at a high temperature, and so if your solvent is close to
boiling it will be hot, so be careful!
• When all of the product has dissolved in the hot solvent, let the solution cool to room temperature and if no crystals
form then scratch the inside of your container again as described above.
• Cool the test tube in an ice bath to maximize crystal formation.
• Dry the crystals on a drying plate or between filter paper and when dry, weigh the crystals. Calculate the percent
recovery from the recrystallization process.
• Calculate the overall percent yield of the purified product in your synthesis.
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2.1.4 Identify and Characterize the Product
• Make sure that you have crushed your crystals!
• Take a melting point range of both the crude and the recrystallized product.
• Take an IR spectrum of your pure product.
characterize the product
2.2 Waste Disposal
• Discard used melting point tubes in a SHARPS CONTAINER!
• Dispose of unused organic chemicals (p-aminophenol, acetic anhydride etc.) in the ORGANIC WASTE CONTAINER
in the back hood
• Dispose of aqueous sample in either the acid or base waste containers as appropriate
2.3 Safety
Because this is a chemistry lab where you will be handling chemicals, accidents and contamination can
happen. It is important you wear your full PPE and be conscious about your cellphone use (which is not
allowed in the lab). Most lab injuries are caused by cross contamination with your gloves or splashes when
transferring solvents. Sometimes you don’t notice your gloves are contaminated and you touch your face or
handle your cellphone. Although we will constantly remind you of the proper use of PPE and lab safety
procedures, if and accident/injury/incident happens and you feel any irritation on your skin due to contact
with the chemicals used in this lab, you need to bring this to the attention of your TA immediately.
Be careful and use common sense when handling the chemicals, solutions, the hotplate and the glassware
when performing this experiment. Do not wear tight pants in this lab. If you spill anything on your pants
the contaminant will be immediately transferred to your skin. Acetic anhydride is a potentially corrosive
chemical, take particular care and attend to any spill involving this chemical immediately.
Eye contact: Remove contact glasses and rinse eyes for at least 15 min in the eyewash while keeping your
eyes open (use WARM water if contact with 4-ethyl aminobenzoate). This can be very uncomfortable so ask
for assistance to keep your eyes open and count the time. Seek immediate medical attention.
Skin contact: Rinse for 15 min in the sink or eye wash (depending on the affected area) with soap in case
of serious skin contact and water. Remove any contaminated items of clothing and shoes. Seek immediate
medical attention.
Inhalation: Get fresh air. If you experience difficulty in breathing, then loosen your tie, belt, collar etc. Seek
immediate medical attention.
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Ingestion: Rinse mouth thoroughly. Do NOT induce vomiting unless indicated by a medical personnel and
seek immediate medical attention.
It is very important to try to remain calm if an accident or injury happens and immediately inform the TA to
receive the appropriate care as needed.
3. Pre-Lab and In-Lab Notebook (10 pts)
3.1 Pre-Lab (5 pts)
You MUST have the following Pre-lab completed in your notebook and checked by the TA at the beginning of lab!
All parts of the Pre-lab must be handwritten IN INK. Include all of the following as part of your pre-lab assignment:
1. Title and date of the experiment
2. Purpose of the experiment
3. Reaction (if applicable)
4. A completed version of the Table below. Look up the molecular structure, molecular weight, melting point and
MSDS information (you may already have this information from a previous experiment, check your notebook!)
Name
p-aminophenol
Molecular
Structure
Molecular
Weight
(g/mol)
Density
(g/cm3)
Melting
Point (◦C)
Weight OR
volume
(g or mL)
Moles
not
applicable
not
applicable
not
applicable
not
applicable
MSDS
(Hazards
Identification)
not
applicable
acetic anhydride
not
applicable
methanol
not
applicable
acetaminophen
not
applicable
not
applicable
The information you will need to complete this table is available from several websites, a good one is the Sigma
Aldrich website (www.sigmaaldrich.com). On the Sigma Aldrich site:
– Search for the compound
– The search will generate a list of different forms of the compound that the Sigma Aldrich sells.
– Choose the link for a pure form of the compound (not a solution, for example), and you should be able to find the
compound’s molecular structure, molecular weight, and melting point.
– Below the compound’s name, there should be a button “MSDS”. Click the button to get a pdf file of the Materials
Safety Data Sheet. Scroll to Section 2.2 of the document (“Hazards Identification”) and write down the relevant
information under “Hazard Statement(s)”.
5. Write in your notebook a response to the following SAFETY Questions
• In this lab, you will be using acetic anhydride, what is the potential danger associated with this chemical?
• What should you do if your skin gets in contact with acetic anhydride?
• Why should you not wear tight pants in this, or any other lab?
6. Complete the Table below using information in Section 2.2 of this packet
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Waste
Used melting point tubes
Where to Discard
Organic Chemicals
Aqueous (water) waste
3.2 In-Lab (5 pts)
See Canvas page for details.
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