201f15 lab manual introduction updated.pdf
TRANSCRIPT
Department of Chemistry
LABORATORY MANUAL CHEM 201 – Fall 2015
Mozol V.J.; Benoit W.L.; Veltri N.L.; Jo, D.L., Sullivan, E.R.,
Wheatley, B.; Mahadev, K.N.; Lefebvre, J.; Sandblom, N.T.A.; Sutherland, T.C.
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TABLE OF CONTENTS – CHEMISTRY 201 LAB MANUAL
Purpose of the laboratory experiment component in Chemistry 201 ......................................................... 3 What should be learned from the wet experiment component of the course? ..................................................................... 3
Laboratory Safety .......................................................................................................................................................... 4 IMPORTANT – First Response Emergency procedures .................................................................................................. 4 Dress appropriately ................................................................................................................................................................... 4 General laboratory policies ..................................................................................................................................................... 5 When performing an experiment .......................................................................................................................................... 5 Additional Laboratory Practices ............................................................................................................................................ 6
Overview of Laboratory Reports .............................................................................................................................. 9 What is required for each laboratory mark? ..................................................................................................................... 9 Pre-‐Laboratory Assignment .................................................................................................................................................... 9 Laboratory Write-‐up .................................................................................................................................................................. 9 Worksheet Lab Reports ................................................................................................................................................................................. 9 Formal Lab Reports ......................................................................................................................................................................................... 9 Report Writing Guidelines ......................................................................................................................................................................... 10 Checklist for the format of formal lab reports ................................................................................................................................... 12
Frequently Asked Questions .................................................................................................................................... 13 How can I prepare for an experiment? ................................................................................................................................................. 13 What if I can't make my scheduled laboratory experiment? ...................................................................................................... 13 What if I withdraw from the course? ..................................................................................................................................................... 13
Chemistry 201 Makeup Lab Section Permission Form ................................................................................... 14
Experiment 1: Determination of percent by mass of NaHCO3 in Alka-‐Seltzer® tablets ....................... 15 Background ................................................................................................................................................................................. 15 Procedure .................................................................................................................................................................................... 16 Worksheet Laboratory Report ............................................................................................................................................. 17
Experiment 2: Determination of Vitamin C Content in Kool-‐Aid® ............................................................. 23 Background ................................................................................................................................................................................. 23 Procedure .................................................................................................................................................................................... 25 Formal laboratory report preparation notes .................................................................................................................. 26
Experiment 3: Determining the Total Acid Content in Kool-‐Aid® .............................................................. 29 Background ................................................................................................................................................................................. 29 Procedure .................................................................................................................................................................................... 30 Formal laboratory report preparation notes .................................................................................................................. 31
Experiment 4: Synthesis of Cholesterol Nonanoate and Preparation of a Liquid Crystal Display (LCD) ................................................................................................................................................................................ 34
Background ....................................................................................................................................................................................................... 34 Procedure .......................................................................................................................................................................................................... 36 Melting Points .................................................................................................................................................................................................. 38
Worksheet Laboratory Report ............................................................................................................................................. 40 Experiment 5: Structure and Physical Properties of Compounds .............................................................. 46 Background ................................................................................................................................................................................. 46 Procedure .................................................................................................................................................................................... 48 Worksheet Laboratory Report ............................................................................................................................................. 50
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Purpose of the laboratory experiment component in Chemistry 201 Chemistry is an experimental science. Most chemists spend their time in laboratories mixing chemicals, analyzing samples and making observations. Experimentally obtained information is needed to support any work a chemist might do at an office desk or in front of a computer. Students often have the misconception that studying chemistry means relying solely on textbook information. Although a large part of chemistry involves reading chemical literature, this knowledge cannot stand apart from experimental observations. Advancements in chemistry start with experimental observations that are then interpreted and explained within the context of existing chemical literature. The importance of understanding experimental techniques and concepts when studying chemistry is reflected by the course requirement of an overall grade of 50% for the laboratory experiments to earn a grade higher than D+. A grade of C- or higher qualifies as a pre-requisite pass. This means upon finishing Chemistry 201 they may register for all higher-level courses that require that course as a pre-requisite. What should be learned from the wet experiment component of the course? In the laboratory, you will learn the techniques and skills that chemists use in a laboratory setting. By the end of Chemistry 201, you should be familiar with and comfortable in a chemistry laboratory. You should learn how to follow procedures and how to perform those procedures quickly and efficiently. Note that there is reasoning behind each step of a procedure. In Chemistry 201 you will not be marked on the success of your experiment. One can get a grade of excellence (A) for a laboratory write-up for an experiment that failed. Rather, Chemistry 201 aims to develop your ability to understand why you are doing an experiment and what you are doing at every stage of that experiment. If an experiment is not successful, you need to recognize where it went wrong and how you might modify it if asked to redo it. It is hoped that you will learn from your mistakes as the course progresses. Keep in mind that you should always be striving to improve your performance with each experiment you do. A good grade in any chemistry course will depend upon this. Future courses, based on their expectation that Chemistry 201 was a pre-requisite for their course, will demand that a student’s experiment was successful for a grade of excellence (A). You must record information about all steps performed in the laboratory. With these notes, you can then leave the laboratory, formulate ideas about the experiment, and then summarize all work in a written report. By the end of Chemistry 201, you should be able to do this for an experiment. The laboratory work and lectures for Chemistry 201 are related. The relationship is not often obvious for the earlier experiments, as they often involve knowledge of Chemistry 201 as a whole. Also, scheduling difficulties for a large enrolment course like Chemistry 201 will often result in the relative timing of the two components being less than perfect. Though this is not always appealing from a student's point of view, remember chemical advancements often involve making observations then reading related information in journals or books.
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Laboratory Safety Safety is the number one priority in any chemical laboratory. The experiments for Chemistry 201 present fewer dangers than most laboratory work, but they still pose a variety of hazards. Some specific precautions are noted in the procedure for an experiment, but all chemicals should be assumed to be hazardous. All undergraduate students taking chemistry laboratories are required to complete an introductory course (approx. 50 minutes) on laboratory safety. You are required to do so before beginning your first laboratory session. This is a federal requirement.
This course can be accessed online. Note that there is a link to this course on your D2L Chemistry 201 site. Please see the pdf file on D2L to troubleshoot any issues before notifying the lab coordinator. Students who have not completed the lab safety course will not be allowed to work in the laboratory. In order to provide you and those around you with the safest possible working environment, the following rules will be rigorously enforced. You will not be permitted in the laboratory unless you comply with these rules.
IMPORTANT – First Response Emergency procedures
o In case of emergency, inform the Laboratory Instructor immediately. If required call campus security 220-5333 for assistance.
o In case of a major fire, pull the nearest fire alarm and evacuate from the laboratory and building.
o Learn the locations of the nearest telephone, fire extinguisher, fire alarm, eye wash station, emergency shower, and first aid kit, as well as exit routes from the laboratory and the building.
Dress appropriately If you are not wearing attire that follows these rules, you will NOT be allowed in the laboratory. As following these guidelines is your responsibility, missing an experiment due to inappropriate attire will result in a mark of zero for that experiment.
• Safety glasses must be worn at all times when in the laboratory. Contact lens wearers run the risk of more serious injury to their eyes in the event of a foreign body or chemical contaminating the eye. It is strongly recommended that contact lenses should not be worn in the lab (i.e. wear contact lenses at your own risk). If contact lenses must be worn, safety goggles must be worn over them.
• Full-length and long sleeves laboratory coats must be worn at all times when in the laboratory.
• Your feet and legs should be completely covered. Pants or skirts that do not completely cover the legs are prohibited in the laboratory. Shoes that do not completely cover the feet are prohibited in the laboratory. This means no shorts, no skirts higher than floor length, no sandals, no open-toe shoes, no slipper-style shoes that leave the top of the foot uncovered, no nylons or tights, etc..
• No hats, caps and toques are allowed.
• Long hair should be tied back so that it does not become entangled in apparatus or hang in Bunsen flames. Your fingers and arms should be free of rings or bracelets.
• Do not wear your laboratory coat in common eating or meeting areas after using it in the laboratory.
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General laboratory policies
• Students are not allowed in the laboratory unless a laboratory instructor is present.
• No unauthorized visitors are allowed in the laboratory.
• Food and beverages are forbidden in the laboratory.
• Unauthorized and overnight experiments are prohibited.
• Cell phones, iPod/iPad and other unnecessary electronic devices, except calculators, are banned in the laboratory.
• Earplugs and headphones are banned in the laboratory.
When performing an experiment
• Pay attention to any hazards and warnings given in each experiment.
• Experiments in progress must not be left unattended.
• Do not damage the labels on chemical containers; do not use chemicals with damaged and/or incomplete labels.
• Never handle or pour flammable liquids near an open flame, hot surface, heat source or other ignition source.
• Use the appropriate apparatus (e.g. a spatula) to minimize skin contact when handling chemicals.
• Never pipette by mouth.
• Harmful or odorous chemicals are to be handled only in a fume hood. Generally, if you find a chemical in the fume hood, use it in the fume hood.
• Wash your hands frequently during the experiment and before you leave the laboratory to remove any chemicals you have contacted.
• Accidents must be reported immediately to the laboratory instructor. Do not panic, and do not try to cover up. Wipe up small chemical spills immediately as directed by the laboratory instructor. Spill kits are available in each laboratory.
• To avoid possibility of chemical spills and accidental skin contact, keep your own work area and the common areas such as chemical dispensing areas, the weighing balances and area surrounding them, the sinks and the fume hoods clean and orderly. At the end of the laboratory period, make sure that both your own and the common work areas you have used are clean and tidy.
• In the event of accidental skin contact, ask a fellow student to inform your laboratory instructor while you immediately start to flush the affected area with copious amounts of cool water.
During the first laboratory period, your laboratory instructor will go through various safety aspects of the laboratory in which you will be doing your experiments. You must acquaint yourself with these in order to complete the "Student Safety Training" Record. This record must be completed, signed, and handed back to your laboratory instructor before the end of the second laboratory period. The laboratory will close promptly at the end of the 3 hours period. This includes a maximum of 10 minutes “overtime” to tidy up.
At the end of each laboratory period, make sure that both your work bench and the common work areas are clean and tidy. Use a brush or broom to sweep up any solid chemical spills and dispose them in the waste container. Wipe down your work bench using a clean wet paper towel. Wash your hands before you leave the laboratory to remove any chemicals you may have contacted.
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In general, safety always has the highest priority. Think before acting and do not rush laboratory work. Remember, “One can get a grade of excellence (A) for a laboratory write-up for an experiment that failed”. Common sense is the most fundamental rule of all. Continually communicate with your laboratory instructor, particularly if unsure of what to do and/or how to do it. Workplace Hazardous Materials Information System (WHMIS) Federal law states that students are entitled to information concerning any materials used in the laboratory. The Materials Safety Data Sheets (MSDS) are available through my U of C Chematix catalogue https://ehssuite.ucalgary.ca/Chematix/. This catalogue is a source involving all chemicals used at this University and information concerning their hazards. Additional Laboratory Practices Accidents must be reported immediately to the laboratory instructor.
Fire
• Know the location of the safety shower, fire extinguishers, fire alarm pull station and the nearest telephone. Do not panic!
• If the vapours from a flask ignite, a small fire can be extinguished by turning off the burner and gently placing a watch glass, wire gauze, or a notebook over the top of the vessel containing the burning solvent. Do not move the flask. If it is necessary to use the fire extinguisher always take the fire extinguisher to the fire.
• If solvent spilled on bench tops ignites, if possible, move bottles and flasks of any solvents away from the vicinity immediately.
• If your clothing is set on fire, do not move around. Stop everything you are doing, go down (drop) onto the floor, protect your face with your hands and roll over and over to smother the flames.
Burns
• Beware of burns from forgotten still-lit burners and hot lab equipment. Remember that the thermometer in the melting point apparatus is at the temperature it records!
Explosions
• Explosions are very fast exothermic reactions and usually occur with substances that can undergo internal redox (reduction and oxidation) reactions or with substances that can decompose to give much more stable compounds. You will be warned if any explosion hazard exists with the compounds that you are using.
If you see this symbol, you must talk to your laboratory instructor before you continue. It means that there are significant hazards that your laboratory instructor needs to check before you continue or there are additional equipment that you need to sign out.
If you see this symbol, you should proceed with extra caution after checking your safety precautions. Check with your laboratory instructor if in any doubt.
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Poisoning, skin contact, chemicals in the eyes
• Several of the compounds you will use are poisonous. The regulations concerning NO eating and drinking in the laboratory must be strictly adhered to.
• Do not pipette liquids by mouth. • Certain harmful, even carcinogenic, substances can be absorbed relatively easily through the skin. Use scoops,
spoons or spatulas when handling chemicals. You may wear disposable examination gloves provided but do not consider these to be impenetrable barriers. If a chemical spills on your hand, remove the gloves quickly and wash your hands. Always minimize contact with chemicals; wash affected areas with water immediately after accidental contact. You should always wash your hands before leaving the laboratory.
• If you splash something into your eyes wash them thoroughly for about 15 minutes at the eyewash station. Contact lens wearer may need to remove the lenses immediately in order to wash the eyes. However, such action may cause more damage to the eyes. In general, wearing contact lenses in a chemical laboratory is not advisable.
• If harmful, irritating or flammable gases are used for or produced during a reaction, then that part of the experiment should be conducted in the fume hood.
Mixing chemicals
• Extreme caution should be used when mixing chemicals. When in doubt, ask your laboratory instructor. • Carefully observe the warnings about mixing water with certain chemicals. For example, water should never be
poured into concentrated acid or brought into contact with sodium. • Be especially careful when dealing with waste, as certain types of waste are incompatible, resulting in
unexpected, difficult-to-control reactions. Organic and poisonous waste should be disposed of in designated containers (e.g. organic waste).
Protection of skin and clothing
• Acids and alkalis are corrosive and will “burn” skin and damage clothing, and certain organic compounds are dyes that will stain surfaces for days. These are the reasons why you are required to wear full-length long sleeves protective laboratory coats and safety glasses. Your legs and feet must also be covered. This means no shorts, no skirts higher than floor length, no sandals, no open-toe shoes, no slipper-style shoes that leave the top of the foot uncovered, etc..
Handling reagents
• Always replace the caps on reagent bottles as soon as you have finished dispensing the reagents. Many compounds will react with moisture, oxygen or carbon dioxide in the air. Other compounds are volatile and will evaporate quickly if the bottles are not capped. Do not mix up the caps of reagent bottles, as trace chemicals inside the cap may react with chemical in the “other” bottle. If you mix up the caps, inform the laboratory instructor immediately.
• Label beakers, flasks, pipettes, etc. to make sure the correct reagents are used. • Do not pipette directly from any reagent bottle. • Always pour from the side of the bottle opposite the label so that the information on the label is not rendered
unreadable. A reagent with no label at best is useless and at worst is dangerous.
Tidiness
• Care and tidiness is an important factor in laboratory safety. Contaminated equipment and untidy work space will affect accuracy of results of experiments.
• Keep your work bench and the common areas, including the side benches where reagents are dispensed, the weighing balances and their surrounding areas the fume hoods and the sinks, clean and neat. Wipe up any spills immediately.
• After completing your experiment, make sure the common work areas are clean and tidy and wipe down your work bench with clean wet paper towel.
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Fume hood use
• Fume hoods are specifically designed to prevent harmful vapours from entering the general atmosphere of the laboratory when experiments are performed by drawing air from the laboratory into the fume hood. They can also be used to provide a safety barrier for more hazardous experiments.
• Before using a fume hood, make sure that it is working (e.g. check that air is being drawn into the fume hood by observing a strip of paper near the fume hood opening; the strip should flutter with the uptake of air).
• Chemicals with strong or noxious odours should always be used in a fume hood – even when weighing! • Equipment that has come into contact with noxious materials should be kept in the fume hood until they are
cleaned. In the worst case they should be cleaned in the fume hood. Equipment such as Pasteur pipettes that can be disposed of in the fume hood or must be cleaned before being disposed of outside of the fume hood.
• Remember that a fume hood only works effectively when the sash is down at or below the indicating level. For optimal performance experimental equipment is set up at least 10 cm from the front edge of the fume hood. Therefore, whenever you are working in a fume hood, try to keep the sash level as low as reasonably possible at all times.
Waste Disposal
This is an extremely serious issue. Before disposing of any waste material, think about what you are doing. Waste disposal rules are intended for your safety, the safety in the laboratory and the safety of the environment. Failure to comply with these rules will lead to you being suspended from working in the laboratory and hence losing laboratory marks. In the worst case, it could lead to dangerous laboratory conditions and result in injury.
Proper waste disposal is important, so make sure waste is disposed of in the appropriate container. Here are the rules:
• Pay attention to the specific instructions for the disposal of chemical waste given in the script for each experiment. When in doubt, check with the lab instructor.
• Never pour waste chemicals down the sink unless instructed by the lab instructor. • Glass waste must be cleaned and disposed of in the specified container. • To clean up contaminated broken glassware, use a brush and dustpan to collect all the pieces in a beaker,
rinse the pieces with water and then dispose them in the blue bucket for broken glass provided in the laboratory. Only clean broken glass can be disposed of in the blue “broken glass” pail. Chemically contaminated glass waste is costly to be disposed of and can pose a hazard to the environment.
• Inform your lab instructor immediately when glassware that contains chemicals is broken. The chemicals must first be contained and neutralized before the glass pieces can be collected and washed.
• Other non-glass sharp objects must be disposed of in containers specifically marked for this purpose. • Inorganic waste must be disposed of into the 20 L barrels provided in the laboratory unless otherwise
instructed by your laboratory instructor. • Organic waste must be discarded into the labelled waste containers in the fume hood. • Pasteur pipettes should be rinsed and placed in the specified container. • Chemically contaminated solid waste (e.g. filter paper and pipette tips) must be disposed of in the specifically
marked containers. • Non-chemically contaminated solid waste (e.g. paper towel) should be discarded in the waste garbage bins. • Never overfill containers. There must be at least 5 cm air space at the top. • The waste disposal area must be kept clean. • If a waste container is full (reached fill line), inform the laboratory instructor immediately.
If in doubt, check the laboratory manual for written instructions. If you are still unclear, ask your laboratory instructor.
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Overview of Laboratory Reports There are five experiments, each worth 20 marks. The entire laboratory component is worth 25% of the final course grade. A student must achieve an overall laboratory grade of at least 50% and must have completed a minimum of 3 experiments to gain a grade of C- (pre-requisite pass) in Chemistry 201.
What is required for each laboratory mark?
Students who in the view of the laboratory instructor (lab TA), engage in disruptive or negligent behavior while performing their experiment will have a mark deducted from their report grade and/or asked to leave the laboratory.
Pre-Laboratory Assignment
• Worth 5 marks; must be completed at least 1h before your lab start time.
Read through the experiment entirely and complete the pre-laboratory exercises posted on the course D2L site. If they have not been completed, you will receive a mark of zero on the pre-lab assignment and you will be asked to leave the lab, as it is hazardous to conduct experimental work without preparation. This is NOT a legitimate reason to get permission to attend the make-up lab time.
Laboratory Write-up • Worth 15 marks; due either in lab (worksheets) or 1 week after lab (formal reports).
There are two formats for the laboratory reports: worksheets and formal reports. Regardless of format, all lab reports must be hand-written in permanent ink (no pencil or erasable pen). Any errors should be crossed out with a single line, so that they remain legible, and corrections written nearby. White-out should never be used in any part of your lab reports. Typing reports or attaching computer-generated graphs is not allowed. Although some experiments are performed in pairs, and partners may share the same set of data, reports must be written and submitted individually. Laboratory reports are subject to the academic regulations in the University Calendar outlined in the Statement of Principles of Conduct section, including the guidelines in the Statement of Intellectual Honesty and Plagiarism/Cheating/ Other Academic Misconduct sub-sections (Section K). If you are struggling to determine if you have followed the principles of conduct as outlined in the University Calendar, ask your course instructor or lab TA to clarify these points before submitting work you are unsure of. Worksheet Lab Reports The reports for Labs 1, 4, and 5 are worksheet style. Print the worksheet pages from your lab manual before you arrive, and fill them out with your data, calculations, and results during the lab period. Be sure to show your work for all calculations in order to receive full marks. Before you leave the lab, staple these sheets together with the experimental procedure pages and hand them in to your TA. While you may prepare some of your work before arriving at lab, the worksheet reports must be handed in during your lab session – no part of the write-ups for Experiments 1, 4, and 5 is completed after lab time. Formal Lab Reports The reports for Labs 2 and 3 are “formal reports”. For these laboratories, print the experimental procedure pages from your lab manual and bring these to lab. You will also need to bring a blue laboratory notebook in which to write your data and report. These are available for purchase from the bookstore. Prepare your notebook before lab by creating data tables and places to write your observations in the last page of the notebook (after the graph paper pages). Instructions for these tables are in the experimental sections and in your pre-lab assignments. During lab you will write all data and observations directly into your notebook. Have your data initialed by your TA before you leave the lab. Failure to do so results in a grade of zero for data and observations. It is also strongly
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advised that you start doing relevant calculations before leaving the laboratory, as you have an instructor there to help start things in the right direction.
The report itself will be written on the first pages of the same notebook that contains the observations. Reports are handed in at the start of tutorial, one week after your lab. If your report is late, it must be handed in to the late-report drop box outside EEEL 239. One mark per day will be deducted from your report grade if you hand it in late. Weekends count as two days. Late reports are collected at 5:00 PM daily – reports submitted at 5:01 or later will be considered as handed in the next day.
As you prepare for the experiment, try to decide what the take-home messages are about the chemical concepts involved. During the experiment, keep these concepts in mind. Ask your TA for clarification if you are having trouble understanding how your experiment fits with these conceptual ideas. Thinking about these chemical concepts at each stage of your laboratory work (preparation, performance, and write-up) will improve your ability to communicate the main ideas in your report.
Report Writing Guidelines A lab report should not take longer than 4-5 hours to generate. Use the guidelines (and order) below to help prepare your formal lab reports. In addition, some experiment-specific requirements are listed within Experiments 2 and 3.
Introduction (3 marks)
Objective The goal(s) of the experiment should be stated clearly and explicitly. Include chemical reactions where relevant. Focus on why you have done this experiment, not just what was done. If there was a Part I and II to the experiment, include objectives for each, and show how they are related to the overall experimental goal.
Techniques and Analysis
In the context of your objective(s), briefly outline the techniques used in the experiment, and how they were important to exploring the goals of the lab. If any particular type of analysis was used, explain why it was useful in this context.
Procedure (1 mark)
Procedure Attach the printed lab manual pages, and make reference to them. Indicate whether there were any modifications made to these procedures, and if so, what they were. Even minor changes should be noted. If no changes were made, state this.
Results (4 marks)
Raw Data Summarize your observations and numerical data as part of the report. Large tables of raw data may be left in the back of the report, but important results should be copied neatly here. When you include a table of data, be sure to include units and label all tables with a descriptive title, as well as rows/columns. You may wish to include final/calculated answers in your data tables as well, depending on the experiment.
Graphs (when appropriate)
Graphs should be plotted by hand on the graph paper pages in the lab notebook. Plan carefully to use as much of the plot area as possible. Have evenly-‐scaled axes with descriptive labels and units, as well as a descriptive title and legend if necessary.
Sample Calculations
For repetitive calculations, you need only show one example of each type of calculation within your report. Use ink, and make sure your work is written neatly (with units) and is easy to follow. Include all equations and show all intermediate steps.
Statistical Calculations (when appropriate)
In some experiments, you will calculate the standard deviation and % error for your data. Show sample calculations, and report values to appropriate significant figures. Provide a correctly cited source for any literature values used.
Final Calculations Show calculations leading to the determination of the final value/major finding of your experiment. Include units & report final answers to the correct number of significant figures.
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Discussion (5 marks)
Experimental Context
State your key findings in context of the techniques and analysis you performed. Review briefly what occurred during the experiment (no need to restate the Introduction or Procedure, but you may reference them if needed). Focus on the “take-‐home” message of your experiment & results.
Accuracy Comment on the accuracy of your key finding(s). If available, compare your value(s) to literature values, and comment on whether they agree. Justify your claim numerically. Remember to cite correctly your sources. If your value is different from the accepted value, attempt to explain why this could be (you don’t have to repeat your “sources of error” section).
Precision and Reproducibility
Discuss the overall reliability of your key findings. If possible, justify your claim numerically. What does the precision of your result say about the reproducibility of the techniques(s) used?
Sources of Error Discuss sources of uncertainty in your experiment. These may be related to flaws in the technique, assumptions that were not necessarily valid, or grievous performance errors. Explain how each source of uncertainty would have affected your results. If possible, suggest a way to remove or improve these uncertainties.
Conclusion (1 mark)
Conclusion Summarize the objective and key findings of your experiment. Explain whether (and why) you consider the objective(s) satisfied, and why, based on the findings in your Discussion. This should be a brief summary; all new information is already in the Discussion.
References (1 mark)
References Provide a listing of the sources you used when completing the experiment and report. Use an in-‐text citation to link references for all specific facts and figures in your report. References could include personal communication, the lab manual, a book, or website. ACS format is summarized in Appendix F, but any standard format is acceptable as long as it is applied consistently for in-‐text citations and the works cited list. Remember that failure to provide suitable references implies that you are claiming the work of others to be your own (i.e committing academic misconduct).
Format and Presentation (applies to all sections)
Format Reports should be legible and coherent. Use a ruler for tables, write in ink, and do not use whiteout. Use correct spelling and grammar – lab reports should be written in third person, past tense as a matter of convention.
Length For experiments in CHEM 201, follow these guidelines: • Introduction: Max. 1 page • Discussion: Max. 2 pages • Conclusion: A few sentences – less than ½ page
The exact length will depend on the relative size of your handwriting, but remember that quantity doesn’t necessarily equal quality!
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Checklist for the format of formal lab reports Before submitting your formal lab report, you can use this checklist as a quick guide to make sure you have met the formatting requirements. Remember, formal reports are graded for overall appearance and for communication of ideas. This checklist is for formatting, mostly addressing only the overall appearance aspect of your report. To perform your best on formal lab reports, you will also need to also adhere to the “General instructions for the content of formal reports” described in the previous section to strive for a complete communication of ideas.
FORMATTING CHECKLIST Yes No
General appearance: Did I fill-in all information required for identification (e.g. name, section number, etc.)?
Is my report written by hand (in ink) in the same blue notebook as the data I recorded in the lab?
Did I use ink, crossing out errors with a single line (and not using whiteout)?
Is everything legible?
Did I check the spelling and grammar?
Did I write in the past tense and in the third person?
Did I include the ALL required sections in the APPROPRIATE ORDER?
Introduction o includes relevant equations? o ~ 1 page in length?
Procedure o superscript number provided, corresponding to number given to the lab
manual reference in References section? o procedure pages from lab manual are attached?
Results
o includes relevant equations? o tables clearly labelled, including titles and appropriate units? o tables include data collected (numerical data and observations) and data
calculated? o sample calculations provided, showing all steps (including all required
equations, with units)? o graphs provided are plotted by hand and include: titles, labelled axes,
appropriate scale (i.e. graph fills as much of the graph paper space as possible)?
Discussion
o ~ 2 pages in length (or less)? o clear progression of ideas (i.e. paragraph style, logical flow, not repetitive
or contradicting)? o units given with all values quoted (for both experimental values and
literature values)?
Conclusion o ~ 1-3 sentences in length? o final result(s) stated—summarizes success of the experiment?
References o consistent formatting (Appendix H)? o numbers match in-text citations?
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Frequently Asked Questions How can I prepare for an experiment? Use the following checklist to be sure you are prepared for your laboratory session. Before your scheduled lab day:
o Read through lab safety information. o Read the appropriate pages of the lab manual for the experiment. Seek further information (from your textbook,
instructor, or laboratory instructor) to clarify anything you are unsure of. o Print the appropriate pages of the lab manual for the experiment (e.g. procedure and worksheet pages where
applicable). You will not be able to do the experiment without these pages! o Complete the necessary pre-lab assignment.
On your scheduled lab day:
o Wear appropriate lab attire1 (see section on Laboratory Safety – Dress Appropriately). o Bring a lab coat and safety glasses (and lab locker combination for experiments 3, 4 and 5). o Bring a printout of the procedure and drawer equipment list. o Bring a printout of the worksheet for experiments 1, 4 and 5, or a blue lab notebook for experiments 2 and 3. o Bring a pen and scientific calculator.
What if I can't make my scheduled laboratory experiment? Any student who feels s/he has legitimate grounds for an excused absence from a laboratory class (e.g. medical), or a valid reason for failing to submit a report on time, should contact the Laboratory Coordinator, Dr. Erin Sullivan, SA 144D, ([email protected]) within 48 hours of the scheduled experiment. Documentation is normally required. In general it is expected that missed experiments will be rescheduled at a later date, otherwise a mark of zero will be given. For an experiment to be rescheduled, written permission must be obtained from the Laboratory Coordinator (complete Chemistry 201 Makeup Lab Section Permission Form and bring to the Laboratory Coordinator). When possible, inform the Laboratory Coordinator in advance if you are ill and do not expect you will be able to attend/submit the lab. What if I withdraw from the course? You must make arrangements to have your lab instructor or lab technician check the equipment in the drawer that was assigned to you. When the lab instructor or technician is satisfied with the condition of the equipment in the drawer, he/she will sign you out of the lab section.
All students, even those who withdraw early from the course, MUST sign out of their registered lab
sections before the last day of lectures of the term.
Any student who fails to sign out of lab will be assessed the “Failure to Check-out” fee of $30.00 plus any accumulated replacement cost of equipment that the student may have damaged or lost.
If this fee is not paid by the last day of the final examination period of the term, an additional $10.00 administrative fee will be charged and university services (registration, transcripts, etc.) may be
withheld.
1 If you are not wearing attire that follows these rules, you will NOT be allowed in the laboratory. As following these
guidelines is your responsibility, missing an experiment due to inappropriate attire will result in a mark of zero for that experiment.
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Chemistry 201 Makeup Lab Section Permission Form
This form must be completed, including signatures from the Lab Coordinator AND Makeup Lab TA, and stapled to the FRONT of the lab write-up to be handed in.
Student Name: ID #:
Registered (Home) Lab Section #: Time: Room #:
Name of Home Lab TA:
Makeup Lab:
Date: Time: Room #:
Name of Makeup Lab Section TA:
Title and # of Experiment to be performed in Makeup Lab Section
Reason for Makeup Change of Lab Section:
Signature of Lab Coordinator:
Approval Date:
Signature of Makeup Lab TA:
Date and Time Experiment was performed:
This information is collected under the authority of and in response to the Freedom of Information and Protection of Privacy Act. It is required for keeping accurate records of students’ attendance. If you have any question about the collection and use of this information, please contact the Lab Coordinator, Dr. Sullivan in SA 144D or at [email protected].