organic chemistry laboratory i chemistry laboratory i ... to introduce students to fundamental...
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ORGANIC CHEMISTRY LABORATORY I
CH 337
Fall 2016
PORTLAND STATE UNIVERSITY
Department of Chemistry
Dr. Alexander H. Sandtorv ([email protected])
Learning goals:
To introduce students to fundamental reactions in organic chemistry
To expose students to fundamental laboratory techniques
To show students how to work independently, safely and reliably
To teach students about good laboratory hygiene, handling of chemicals and safe
working procedures
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Contents
Lab schedule ....................................................................................................................... 3 Before Attending the First Lab Day.................................................................................... 5
Course Grading ................................................................................................................... 7 General ............................................................................................................................ 7 Lab reports ...................................................................................................................... 7 Lab Technique ................................................................................................................ 7 Pre-lab ............................................................................................................................. 9
Laboratory policies ............................................................................................................. 9
Laboratory safety and safety protocols ............................................................................. 11
General safety ............................................................................................................... 11 Fires............................................................................................................................... 12 Spilled Acids and Bases ................................................................................................ 12 Cuts ............................................................................................................................... 13
Handling chemicals and Chemical Waste ......................................................................... 14 Handling chemicals ....................................................................................................... 14 Labels ............................................................................................................................ 15
Handling chemical waste .............................................................................................. 16 Practical Advice ................................................................................................................ 17
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Lab schedule
Schedule
Week Week
start Experiment
Learning goals
1 09.26 Check-in and Recrystallization of Adipic
Acid
Recrystallization and melting
point techniques
2 10.03 Melting Point Analysis and TLC to
Determine an Unknown Sample
Melting point analyses and
TLC analyses
3 10.10 Reduction of Benzophenone with NaBH4 Reduction reactions, IR-
spectroscopy
4 10.17 Extraction of caffeine
Natural products, extraction,
sublimation
5 10.24 Oxidation of Benzaldehyde Using Bleach Oxidation reactions,
extraction, IR-spectroscopy
6 10.31 Distillation of a Mixture of Unknown
Composition
Distillation, analytical
7 11.07 Acetylation of Aniline Acetylation reactions,
distillation, 1H-NMR
spectroscopy
8 11.14 Synthesis of Cyclohexene from
Cyclohexanol
Elimination reactions,
distillation, 1H-NMR
spectroscopy
9 11.21 SN2 reaction of 2-naphtol and 1-
iodobutane
SN2 reactions, TLC-
monitoring, IR-spectroscopy
10 11.28 Check-out and make-up lab
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TAs
Day Time Section TA Email
M 1.00 p – 4.50 p 016 Jackie Slack [email protected]
1.00 p – 4.50 p 017 Hayley Irving [email protected]
5.40 p – 9.30 p 911 Rory Gallagher [email protected]
5.40 p – 9.30 p 912 Jackie Slack [email protected]
T 8.00 a – 11.30 a 021 Aleksandra Nilova [email protected]
1.00 p – 4.50 p 026 Sunil K. Sundalam [email protected]
1.00 p – 4.50 p 027 Jiries Meehan-Atrash [email protected]
W 8.00 a – 11.30 a 031 Aleksandra Nilova [email protected]
8.00 a – 11.30 a 032 Hayden Winter [email protected]
1.00 p – 4.50 p 036 Hayley Irving [email protected]
5.40 p – 9.30 p 931 Rory Gallagher [email protected]
5.40 p – 9.30 p 932 Hayden Winter [email protected]
R 8.00 a – 11.30 a 041 Luke Lutkus [email protected]
1.00 p – 4.50 p 045 Luke Lutkus [email protected]
1.00 p – 4.50 p 046 Jiries Meehan-Atrash [email protected]
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Before Attending the First Lab Day
Please read the following information carefully.
Experiments begin on the first day of lab
Safety goggles are required for all experiments, including the first experiment.
The chemistry stockroom sells the following goggles:
- Pyramex Capstone Goggles: $15
- UVEX V-Maxx Goggles: $8
A notebook is also required for all experiments. Notebooks can be purchased
from the chemistry stockroom (Composition notebook: $3)
You are expected to finish all required pre-lab exercises before attending each lab.
These are:
- Know the risk and safety precautions associated with all chemicals
handled for that week’s experiment
- Reading the experiment carefully and familiarizing yourself with the lab
- Complete a multiple choice quiz online (must be done before the lab
starts. The quizzes are time stamped online).
- Watching a web lecture (webinar)
If the required pre-lab exercises are not finished, you are excused from the lab
until the required assignments are finished. You will also receive 0 points for the
pre-lab assignment.
You must bring a hard-copy of the procedure, either a directly printed version or a
hand-written copy.
Attendance in this lab is mandatory. You must attend all scheduled laboratory
sessions. The labs closing time is strictly enforced, no students are allowed to
work overtime.
If a personal emergency occurs, please contact the professor ([email protected])
as soon as possible.
You are expected to fully read the syllabus and familiarize yourself with all
concepts described herein.
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Repeated phone use is not allowed for non-lab purposes.
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Course Grading
General
The total grade for this course is assigned as follows:
Lab Reports 50% Pre-lab 10%
Lab Technique 40%
Please note that there is no curving of grades in this course.
Grades
Grade Points Grade Points
A 100-95 C+ 69-68
A- 94-90 C 67-58
B+ 89-84 C- 57-55
B 83-74 D 55-45
B- 73-70 F <45
Lab reports
Reports must be typed in the format provided in D2L and must be handed in one lab
period after the experiment is completed. Reports must be handed in at the start of the lab
period.
The reports will be graded by your TA and returned to you with clear comments and
scores. An annotated copy of the report form is provided in D2L with helpful comments
about how to best compose a lab report. Your TA will also be available to give you
feedback if necessary. The grading of the reports is based on a rubric and meetings
between the TA-pool and the professor.
Lab Technique
You will be evaluated on your lab technique and performance by your TA. For each lab
session, you can receive a total of 40 technique points, based on four categories worth ten
points each:
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Is the student able to work in a safe manner? (Safety)
Safety is a number one concern when working in the lab. Safety awareness means
handling and disposing chemicals in a reliable manner, always wearing appropriate safety
attire (lab-coat and goggles) and following instructions from the TA and webinars /
manual. Unsafe behavior can be: touching face and key-board with gloves, wearing lab-
coat and/or gloves in the hallway, not setting up experiments as described or handling
chemicals in a way that is considered unsafe. Maintaining a neat and safe working space
is also part of safety.
Is the student able to work independently? (Independence)
We want to encourage students to ask questions and approach the TA if they feel unsure
or want to discuss any facet of the chemistry, but we also wish to encourage students to
think critically and make good and independent decisions on their own. Simple
procedural questions that can be answered by reading the lab journal or adequately
preparing should be kept to a minimum. Adequately preparing by reading the manual and
carefully watching the webinars is expected.
Is the student able to carry out laboratory procedures and apply laboratory techniques in
a reliable way? (Effort)
In CH 337, we are focused on teaching students standard laboratory procedures and
protocols, such as extraction, distillation, melting point analyses, and so on. Students that
follow instructions and perform the laboratory procedures in safe, reliable ways will
therefore receive points in this category. The webinars should provide the necessary
background to prepare.
Is the student able to complete the experiment with reasonable success and within the
time allocated? (Completion)
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An important aspect of laboratory work is time-management. Each experiment in the
course portfolio can be completed within the allotted time, as long as students are well-
prepared and work in an efficient manner. We also wish to encourage careful laboratory
work and award points when students are able to perform the experiment with reasonable
success.
We wish to highlight that the technique grade is not to give penalties, but to properly
award good behavior and to emphasize proper laboratory practices.
Pre-lab
There are four components to each pre-lab exercise that you are required to complete
prior to attending the lab: reading the lab manual, looking up safety information for
relevant chemicals, viewing a short webinar regarding the experiment and answering a
multiple-choice quiz. The latter two are available on D2L. A maximum of 10 points can
be rewarded. Your pre-lab grade is calculated based on the percent score (y) achieved on
the quiz
Pre lab grade = y/100 x 10
You are expected to be familiar with the concepts raised in the webinar, as your TA will
not spend in-class time discussing the issues addressed in the webinar. If you clearly fail
to follow the instructions raised in the webinar, your TA will decrease your technical
score. In severe examples, your TA might also excuse you from lab.
Laboratory policies
What happens if students do not complete their pre-lab assignments?
Students are excused from the lab until the pre-lab has been completed and they receive
no points for the pre-lab assignment.
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What happens if students show up late?
If the students are more than 5 minutes late, they lose 20 points from their technical
score. If they are later than 30 minutes, they are excused from the lab. This counts as one
missed lav.
What happens if students miss a lab?
Students are only allowed to miss a lab if there is a medical emergency, or an emergency
of similar nature. The student must let the TA and professor know immediately. Make up
labs are offered during check-out. Missing two labs is an automatic no pass.
What happens if the student wants to change labs permanently?
Permanent lab changes are only allowed under special circumstances.
What happens if students hand in reports late?
A penalty of 5 points per day is subtracted from the total score of the report. If the report
is not handed in one week after the assignment was due, the student receives a 0 on that
report. After two reports not handed in, the student cannot complete the course.
Please note that lab reports are handed in at the beginning of lab. If the reports are handed
during or after lab, this counts as one day late.
What happens if students are found to have plagiarized material, either from sources, or
from lab-mates or other individuals?
Copying any material without clearly stating the source of such material is considered
plagiarism. This includes, but is not limited to: the internet, books, written materials, and
material written by class-mates, former students, professors or other teaching staff.
Sections of text that are found to be identical or near-identical with respect to content and
information (but not necessarily word-by-word copies) are also considered plagiarism.
It is the professor’s discretion what penalties will be instated on a case-by-case basis.
Point deductions might be introduced, or in severe cases, expulsion from the course.
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Laboratory safety and safety protocols
General safety
The most important aspect in the laboratory is the safety and well-being of the people that
work there. There are several safety features associated with this lab course:
Goggles and lab coat should be worn at all times.
Dress appropriately for laboratory work. You must wear
shoes that cover your entire foot, including the heel. They should fit
up near your ankle; leather is preferred but any non-porous material
is okay. Your clothing must cover your torso and legs down to your
shoes. In addition, you are required to wear a department provided lab
coat while working in the lab. If you show up for lab in inappropriate clothes, you
will be asked to leave and this will count as a missed lab.
Avoid wearing contact lenses.
Know the location of the following:
- fire extinguisher
- fire blanket
- first aid kit
- safety shower
- eyewash fountain
- all exits
No eating or drinking in the lab.
We generally provide nitrile gloves for handling chemicals. Please note that the
protection offered by these gloves, is minimal and most organic liquids and some
solids penetrate the nitrile layer readily.
Do not touch keyboards or phones while wearing gloves. Do not touch face with
gloves.
If you find a mercury thermometer in your drawer, please notify your TA. These
should be exchanged for other thermometers immediately.
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Fires
- Most organic chemicals are flammable
- If organic solvents are spilled, soak the solvents up with a paper towel and leave it
in the hood to evaporate. Never dispose of solvents in the waste bin or down the
sink.
- Never pour organic solvents around a hot plate in use.
- If a fire occurs, inform your TA immediately.
- If clothing catches on fire, inform your TA immediately. Walk the individual to the
safety shower or roll them in a fire blanket to extinguish the flames.
- For small heat burns hold the burn under cold water for 5-10 minutes. Please report
all burns to the TAs.
Spilled Acids and Bases
- For spills of dilute acids and bases, wash your skin under running water.
- For spills of concentrated acids and bases, immediately wash the contaminated skin under
running water for five minutes. Report the incident to your TA.
- For spills of concentrated acids and bases on clothing, remove the clothing immediately.
Report the incident to your TA.
Chemical splashes in the Eyes
- Immediately wash your eyes at the eyewash station. It is imperative to keep eyes open
(sometimes by force) and let the water run over the eyes for at least 15 minutes. Contact
your TA and seek medical attention.
Inhalation of Organic Fumes:
- If an individual inhales a large amount of organic fumes, report it to the TA.
- The individual should immediately be moved to an area with fresh air.
- If the individual stops breathing, call campus safety (503-725-4404) and 911.
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Cuts
- For small cuts, rinse the affected area under running water and apply a bandage from the
first aid kit. Contact your TA.
- For larger cuts or strong bleeding, contact your TA and call campus safety (503-725-
4404) for medical attention.
- Notify the professor or stockroom personnel if any blood is spilled in the lab so that
proper cleanup and disposal procedures may be followed.
Broken glass
- Do not remove any broken glass from the lab, and do not bring it to the stockroom.
Broken glass is immediately placed in the broken glass waste.
Evacuation
- If evacuation of the lab is necessary, leave through any door that is safe or not obstructed-
doors that lead to other labs may be the best choice.
- Leave the building by the nearest exit and meet your TA on the field next to Hoffmann
Hall.
- This would also be the meeting place in the event of an earthquake or other emergency
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Handling chemicals and Chemical Waste
Handling chemicals
The major safety hazard when working in a chemical laboratory is the handling of
chemicals.
- As part of your pre-lab assignment, you should know the risk and safety
precautions associated with all chemicals handled for that week’s experiment.
- Safety information is available by using the chemical’s Safety Data Sheet (SDS).
The SDS can be downloaded from www.msds.com free of charge.
- For a large chemical spill stand under the safety shower and flood the affected
area with water. Remove clothing to minimize contamination with the chemical.
- If any chemicals are spilled, consult your TA immediately.
- If a mercury thermometer breaks, notify your TA immediately. It might be
necessary to evacuate the lab. Do not attempt to clean up on your own
- Chemicals should not be handled on the bench
- Never pick up a bottle by its lid
- For liquids, do not place your own pipet, dropper, or spatulas into the reagent jar.
Pour a small amount into a beaker and measure from that
- Never put any excess reagent back in the reagent jar.
- Never taste a chemical or solution.
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Labels
Chemicals in our laboratories have been marked with the following labels.
(1) Name of chemical
(2) Pictograms depicting the various health and safety hazards associated with the chemical
(3) Health statements
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Handling chemical waste
- All chemical waste must be disposed of in a proper way, and in general, no waste
generated in the lab should go down the sink.
- There are four chemical waste categories, all available in your fume hood. Each
experiment has a specific description of where waste should be placed. Ask your TA if
unsure.
Organic waste
Halogenated waste (only appropriate for a few experiments)
Solid waste
Aqueous waste
- There are also waste bins available outside of the hoods. These include:
General waste bins (none of the chemicals handled should be placed in this bin)
Broken glass container
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Practical Advice
During the laboratory course you will become acquainted with organic reactions and
purification techniques. You will also learn about how to be a productive and respectful
member of a laboratory. This primer will help guide you through many of the techniques
and “rules” you should learn during your time in our organic chemistry labs.
- How to clean glassware: Most of the reagents used in your labs will be readily
soluble in either a very polar inorganic solvent (such as water) or a polar organic
solvent (such as acetone). An acetone squirt bottle is in your hood to aid with
rinsing glassware. All acetone rinse waste should go into the organic waste
container in your hood. Acetone should never be used out of the fume hood and
should never be poured into the sink. After rinsing with acetone and letting it dry,
the glassware can be washed at the sink with soap and water if necessary.
- Upkeep of hot/stir plate: wipe down surface after it cools with a damp sponge.
- Cleaning a hood at the end of class: wipe down the hood with a moist sponge to
remove any solid residue or sand, then dry the hood with a small paper towel.
Spills should be cleaned up using proper techniques during the lab.
- The uncertainty of spilled materials left out: If you spill something, clean it up. If
you do not know how to clean it up, ask your TA. If you spill a large amount of
material, consult your TA. Here are some basics:
Acids: Shake spill neutralizer on this spill until liquid is covered and
fizzing stops. Pick this up by brushing onto a piece of paper and put it into
the trash. Use a wet paper towel to pick up any residue.
Solids: scoop the solid up and put into the solid waste jar. Pick up
remaining residue using a moist paper towel and throw it away in the
trash.
- Gloves: Please be aware that nitrile gloves do not provide protection against most
organic solvents. Change gloves every time something has gotten onto the glove,
with stress put on prevention of contamination rather than the gloves providing
protection. Wearing the same gloves for longer periods of time is not good
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practice, because many contaminants can diffuse through the glove over time. Do
not touch your face with gloves.
- How to weigh solids: Solid should not be added to a receptacle (weigh boat) that
is already on the scale. The receptacle should be removed from the scale after
taring, have solid added to it, then placed back on the scale for reweighing.
Repeat as necessary until desired amount is acquired.
- Proper salt plate cleaning technique: Do not get water on salt plates, they are
made of compressed sodium chloride and will dissolve. After a salt plate is used,
the sample should be wiped from the salt plate using AR acetone (which is
acetone of a higher purity) and folded kim-wipe. Rub the salt plate on/with the
acetone moistened kimwipe, then on a dry area of the kim wipe. Use DCM with
extreme caution.
- Use of solvent/acid pumps: Chemical resistant pumps (cost: $600-900) are used in
the lab to aid with dispensing small amounts of liquid reagents. As long as the
pump is set to the desired volume, they accurately dispense even a small amount
of liquid.
These flammable (red) and general (yellow) pumps work by gravity. Pull
the plunger up, then release and watch your solvent being dispensed. The
acid (green) pumps work by pressure. Pull the plunger up, then depress the
plunger until it stops.
- Using sodium sulfate to dry a liquid: add sodium sulfate(s) to your liquid in small
amounts until the sodium sulfate is free flowing instead of clumping. You do not
need to weight sodium sulfate out, just scoop a little directly into your container.