GENERAL REMARKS ON LABORATORY WORK by iht11609

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									             GENERAL REMARKS ON LABORATORY WORK ,
                   RECORD KEEPING, AND REPORT WRITING

                                       by J.C. de Paula, J.P. Chesick, F.R. Blase,

                                                     R.C. Scarrow, and T.L. Newirth



1.      INTRODUCTION
         Chemistry is an experimental science and, as such, one cannot appreciate its beauty
without spending some time in the laboratory. One of the principal aims of the experiments in this
course is to introduce you to experimental physical chemistry. You will learn to use quantitative
glassware, electronic balances, computers, and spectrophotometers. You will also be trained in
proper record keeping and in the writing of accurate, concise, and informative reports. Another
aim is to show you how these basic skills may be applied to the solution of problems of current
relevance, particularly those related to biological and environmental aspects of chemistry. In the
end, you will have some idea of the difficulties and the painstaking effort involved in gaining
reliable scientific results.
         The keys to successful laboratory work are: safety, preparation, concentration,
cleanliness, alertness, and a calm demeanor (even when faced with adversity). You will note that
safety was mentioned first. That is because it should be always on your mind from the minute you
walk in the laboratory. A sound knowledge of safety rules will eliminate much of the anxiety
associated with laboratory work. Let us review the safety guidelines, which we must follow this
semester.


2.      LABORATORY SAFETY
         The following rules are designed to help ensure that all work done in the laboratory will
be safe for you and your fellow students. No set of rules can cover all possibilities. There is no
substitute for watching and thinking about what you are doing. Here are some notes on safety:

        LABORATORY HOURS. You are expected to come in for laboratory work every
Tuesday and Thursday, from 1 pm until about 4 pm. You may not conduct experimental work
unless one of the instructors is around to assist and supervise you. Fellow students may not
supervise your laboratory work. You may perform computational chores at any time of the day
without supervision.
Chemistry 302                            General Remarks                                    page 2


        EYE PROTECTION. Glasses or safety goggles must be worn at all times while in the
laboratory. Contact lenses may not be worn because they offer no protection and may trap
splashed or splattered liquids, increasing possible eye damage. Safety glasses or goggles may be
obtained from the chemistry stockroom in case you do not wear glasses. Any student not
wearing eye protection in the laboratory may be dismissed from the laboratory by the instructor.
        If any chemical comes in contact with the eye, the most effective first aid is the immediate
flushing of the eyes with a stream of cold water from a faucet at a sink.

        SAFETY SHOWERS. Be aware of the location and operation of safety showers. If
you or a colleague has a bad chemical spill on clothing or hair, or clothing catches fire from a
burner flame, douse yourself or help the person in need to do this in the safety shower.

        CLOTHING. Bare feet are not allowed in the laboratory because of the occurrence of
broken glass and spilled chemicals on the floor. Tops of bare feet are also the most likely
recipients of spilled chemicals. With this in mind, it goes without saying that open sandals are also
not allowed in the laboratory. In order to prevent contact of corrosive chemicals with the skin, I
recommend that you keep as much of your body covered while in the laboratory as possible. A
laboratory apron is often an appropriate means of protection for your clothes as well as your skin.

       PIPETING. Under no circumstances whatsoever are you to pipet by mouth. Most
chemicals are highly toxic. Most people will also dribble saliva into the pipet, thus increasing the
chance of sample contamination.

         LABORATORY BENCHES. Never put food down on a laboratory surface, or eat in
a laboratory, and always wash your hands thoroughly between doing any laboratory work and
eating any food. Apparently clean lab benches may have residues of chemicals (for example
invisible mercury droplets from a broken thermometer) which can be picked up by food items.
Please do not put your bookbags on the benches for two reasons: (i) you may contaminate it
with chemicals that you will then bring home to you and your roommate, and (ii) they occupy
valuable workspace.

         FIRST-AID. Bring any injury (cut, burns, etc.) and spills to the immediate attention of a
laboratory instructor. In the interest of providing immediate medical attention to any possible
injuries, it is imperative that you never work alone in the laboratory. There should always be
another person in the immediate area who is aware of your existence and what you are doing.

        PROPER BEHAVIOR. It is obvious that horseplay is not allowed in the laboratory.
Students engaging in any kind of horseplay will be dismissed promptly from the laboratory.
        You should never hurry through an experiment, no matter how pressed for time you may
think you are. Haste usually leads to bad results or, more importantly, to injury.

        HOUSEKEEPING. Cleanliness and safety always go together, so we request that you
follow these guidelines:
Chemistry 302                            General Remarks                                    page 3


     •   Never add reagents to containers while they are on the pans of the analytical balances.
         Some spillage results in the course of a day, equipment corrodes, the risk of injury
         increases, and many suffer.
     •   Never return unused chemicals to reagent stock bottles. Be sparing in the amounts you
         take. Return for more if needed.
     •   Never insert pipets or medicine droppers into reagent bottles to avoid the possibility of
         contamination of community supplies. Do not lay bottle stoppers down on the bench
         where the stopper can either pick up impurities or contaminate the bench surface.
     •   Read carefully the label before taking any reagent, and record the concentration on the
         label; it may not be exactly that suggested in the laboratory directions.
     •   Keep your laboratory bench and communal areas free of clutter and well-organized. This
         will decrease the risk of spillage, breakage and, consequently, injury.
     •   The person using a piece of equipment is responsible for its cleanliness. If you come to a
         balance or other piece of equipment and it is messy, either clean it or find the person who
         left it that way and ask him/her to clean it. Work done with a messy balance or other
         piece of equipment is evidence of poor laboratory technique.
     •   If you are not familiar with some of the equipment, ask the instructor or an assistant about
         its proper use.

        In designing the experimental procedures and the laboratory, we have attempted to
minimize the risk of injury. Having laid out a plan for prevention above, let us now describe some
guidelines for handling emergencies.

                               EMERGENCY PROCEDURES

             •   Notify the instructor or a fellow student of the accident.
                 If you believe that doing so may delay proper action,
                 then
             •   Take whatever action is necessary to minimize injury to
                 you or others.
             •   While the instructor is tending to the accident, leave the
                 room and encourage your fellow students to do so, as
                 well.
             •   Go to the nearest and safest campus phone and notify
                 the Haverford College Security Department:


                                       DIAL 1111

3.       PREPARING YOURSELF FOR AN EXPERIMENT
        By reading and understanding the safety rules above, you have already done much to
prepare yourself for laboratory work. The next step is to familiarize yourself thoroughly with the
Chemistry 302                              General Remarks                                        page 4


specific experimental procedures before you even set foot in the lab. In this course, this means
reading and understanding the laboratory handouts prior to the lab period. If you have any
questions about the handout, see the instructor as soon as possible or ask questions during the
pre-lab discussion.
          There is no excuse for failing to read the handout before a laboratory period. At least
one week before the experiment is to be conducted, the handouts will be available for
downloading from the course’s web site (http://www.haverford.edu/chem/302/302.htm).
          After reading the handout, you will want to write down in your laboratory notebook an
outline of the procedures. In doing so, you are saving laboratory time! Instead of leafing through
many pages to find out what to do next, all you have to do is glance at a page in your notebook.
Because you understand the procedures, you know exactly what is entailed in performing each
task in the outline. Your every action is planned out and you can go about acquiring data very
efficiently. Some of you will find beauty in efficiency itself, others will relish getting out of lab in as
little time as is necessary to obtain good data.
          Please do not mistake efficiency for haste. If you hurry through a procedure, you are
likely to forget important details, or injure yourself (or others). Carry on at a pace that is
conducive to good data, and count on your instructor's patience and understanding.


4.      THE LABORATORY NOTEBOOK
        In all scientific activity, it is important that accurate written records be kept. The record
must be organized in some way, must be complete, concise, and readable. For this purpose, a
bound notebook is customarily used. All entries should go immediately into this notebook. They
must not be recorded first on odd scraps of paper and then copied into the notebook. This is
poor procedure since it runs the risk that significant information will be lost.
        Your notebook should be complete enough so that you could go back to it in several
years time and be able to re-construct what you did and re-calculate your results. Ideally,
someone else familiar with the procedures should be able to do so as well. All raw data should
be included: chemicals used, concentrations, weights, volumes of materials added, instruments or
volumetric glassware used, etc. Use common sense, however, and do not record trivial
information, for example the size of the glove that you are wearing. All observations should be
recorded. For example:

        ".... B was initially colorless. Upon addition of the pale green A, a blue
        color was noted. Occasionally, white particles were seen, but these
        disappeared upon stirring. Upon further addition of A, a white
        precipitate formed..."

        Be alert for unexpected or incidental phenomena and record these. They can often
provide clues as to why an experiment turned out the way it did.
Chemistry 302                          General Remarks                                 page 5



4.1    GUIDELINES FOR RECORD KEEPING
     I recommend the following procedures for accurate record keeping in the laboratory.
Remember that the better your records, the more complete and impressive your reports will be.

   •   Put your name, address, and phone number on the cover of your notebook.
   •   Leave space at the front for a table of contents.
   •   Number the pages of your notebook.
   •   Enter all pertinent information in detail. Make sure to enter all data and the method by
       which it was taken. If in doubt about whether or not to record something, record it. If
       the information is needed at some later time, you will have it.
   •   Enter the type of equipment used, and the manufacturer.
   •   Record the accuracy of any volumetric glassware (e.g., "50 mL buret graduated in 0.1
       mL was used").
   •   In recording data, record only the significant figures.
   •   Date the pages of your notebook.
   •   Cross out discarded data lightly. You may want to read them later. When discarding
       data, note why you did so.
   •   Label all samples. Feel free to devise your own system. For example, I may label a
       sample JP-145-B, where JP are my initials, 145 is the page number where the entry was
       made, and B indicates that this sample supersedes JP-145-A.
   •   Data collection for similar experiments should be arranged in tabular form, if possible.

    On the following page you will find a sample page of a laboratory notebook, where some of
the points outlined above have been used. Please do not hesitate to ask questions about record-
keeping procedures if you are not sure about any of the above.
 Chemistry 302                                   General Remarks                                           page 6




                    SAMPLE LABORATORY NOTEBOOK PAGE




                                                              Page Number: The key to the
               Date: Important? You’d
                                                              labeling system! All material labels
               better believe it!
                                                              and run labels are referenced to what   Page 15
                                                              page you’re on!

   8/27/98                                   Experiment #2 - Titration of an Unknown
                                                       Brief Outline, written before lab, is often helpful, but does
   Planned         Procedure              not substitute for later recording what is actually done.
        1)          Obtain unknown from professor
        2)          Accurately weigh sample of approx. 0.3 g
        3)          Dissolve sample in 50 mL water
        4)          Add indicator
        5)          Titrate with standard NaOH to pink endpoint

   Results:
   A n u n k n o w n w a s o b t a i n e d f r o m t h e p r o f e s s o r a n d l a b e l e d D G - 15 - A.
   Three samples were weighed out as follows                            Mistake? Strike out lightly, insert
                                                                           corrections and date it (if made on a
            S a m p l e D G - 15 - B               Gross 0.7029 g          later date)! If necessary, note why
                                                                           you made the correction. Remember:
                     Tare is weight of empty       Tare 0 . 4 3 2 1 g      neatness does not count, but
                     vial, cap, and label..        Net 0.2708 g            accuracy and honesty do!!


   Titration DG - 15 - 1 . S a m p l e D G - 15 - B w a s p l a c e d i n a b e a k e r a n d
   Three drops of phenolphthalein indicator solution were added. The
   NaOH (Lot #811-A) with a class B Fisher buret. Starting buret
   o f p i n k i s a t 2 6 . 7 3 m L ( ± 0 . 0 2 m L ). F u r t h e r a d d i t i o n l e a d s t o

   Titration DG - 15 - 2                   S a m p l e D G - 15 - C was ............
                                                                     Sample Numbering (your initials -page #-
                       Analysis of Data                              letter): A label containing this designation is
                                                                     placed on the vessel containing the sample.
                                                                     The sample is instantly identifiable to anyone
                     Analysis and Discussion Sections:               reading your notebook (including you).
Lot number:          Why not do these in your notebook
Important in         first, as a draft for your lab report?
tracking down
inconsistencies.
Chemistry 302                            General Remarks                                     page 7




5.      THE LABORATORY REPORT
         Writing is an integral part of academic life. Hence, it is our goal in this course to develop
not only your laboratory skills, but also your language skills, as they apply to scientific writing.
Generally, the writing style of a scientific article will differ significantly from styles used in the
Humanities and Social Sciences. Some of the practices used in English or History courses do not
apply to scientific papers. For example, although clever symbolism may enrich a narrative, the
scientist must present all facts pertinent to a result in a logical and unambiguous fashion. Also,
scientists use the passive voice almost exclusively. Your English professors will not agree with
this practice, but I recommend that you follow it nonetheless. Finally, a laboratory report should
not be the product of stream of consciousness. I recommend that you write a draft of your report
and that you edit this draft until the discussion is organized and makes sense.


5.1     HONOR CODE REQUIREMENTS
         Since students are encouraged to work together in the course and often work as partners
in the laboratory, many questions arise each year about laboratory reports and the requirements
of the Honor Code. The following is an attempt to make clear the faculty member's expectations
concerning laboratory reports.
         Each student is expected to write his/her own laboratory report. Partners may not write
one report and submit two copies. Also, all computations and questions asked on the lab
handouts should be answered individually. If you consult a literature source, you must give credit
to the source (research articles, textbooks, monographs, web sites, etc.). If you consult with a
student who has had the course previously or read a laboratory report from a previous year, you
must give credit to this source. Your laboratory grade should be based on your work, not that of
someone else, so that if you rely heavily on the laboratory report of a student from a previous
year, you must expect your laboratory grade to show some reflection of that reliance.
         The instructor will assume that everything in your report which is not attributed to another
source is your work. If you abide by the following, there should be no problems:

        a.   Write your report yourself.
        b.   Give credit to your sources.
        c.   Do your own calculations, and answer questions in your own words.
        d.   When uncertain, consult your instructor.


5.2     REMARKS ON STYLE
        Here are general points about style:
Chemistry 302                          General Remarks                                    page 8


       •   Your laboratory report must be word-processed. The text should conform to the
           accepted rules of English spelling and grammar. We require that complete sentences
           be used and that outline format be avoided.
       •   If you know how to use a molecular graphics program, such as ChemDraw, please
           feel free to use it as appropriate. However, structures and mechanisms may be hand-
           drawn.
       •   We strongly encourage you to use Microsoft Word's symbol font and equation
           editor. However, equations and symbols may be hand-drawn. Please do not
           attempt to substitute an odd collection of characters for a symbol. For example: (i)
           /_\ and D are not appropriate substitutes for ∆; and (ii) the notation 1.0E-5 is not to
           be used instead of the correct 1.0 x 10-5.
       •   The main point of a scientific report is to describe the results and discuss the
           conclusions of a set of experiments. You should use your own words to convey the
           message. Direct quotations from textbooks, monographs, or other journal
           articles are not permitted.
       •   The laboratory report for this course should describe the results and conclusions in
           enough detail that any reasonably well-educated chemist off the street can
           understand. It should not contain cryptic references to handouts or lecture notes.
           Yet, the report should be concise; in the context of our course, any laboratory
           report exceeding fifteen pages of text is probably too long.
       •   For general formatting of the report, and for proper use of scientific language, we
           suggest that you follow the guidelines put forth by the American Chemical Society.
           These may be found in the ACS Style Guide, which will be placed on reserve in
           Stokes Library. If the Guide does not answer your questions, then consult one of the
           instructors or ACS publications, such as the Journal of the American Chemical
           Society.
       •   Your report should be divided into sections: title, abstract, introduction, experimental
           section, results, discussion, acknowledgments, and references. These are discussed
           in detail below.

         TITLE. The ideal title consists of one sentence describing the system and/or technique
you studied. Example: "Chymotrypsin: Catalytic Efficiency and Thermodynamic Stability"
is a viable title for a report on the first project in the course.
         Immediately below the title, the names of all authors should be given. Co-authors are
those persons who contributed significantly to the experimental work and interpretation
of results. For the purposes of our course, each student should submit his or her own lab
report. The by-line should show the writer's name first, followed by an asterisk; the names of
collaborators should follow immediately. Example:

                                   Spectroscopy of the Sun

                             Marie Curie* and Gerhard Herzberg
                             Chemistry 302b, Haverford College
Chemistry 302                           General Remarks                                   page 9




          In the preceding example, Curie and Herzberg worked together on the experiment, but
Curie wrote the report. Herzberg should turn in a separate report, where his name appears first,
with the asterisk. Minor contributors should be acknowledged at the end of the article (see
below). Use your best judgment and the honor code guidelines in deciding whose name goes on
the title page; if in doubt, ask the instructor.

        ABSTRACT. The abstract is a very concise summary (no more than two moderately
sized paragraphs) of the experiment, including methods, important results, and conclusions.
In principle, the reader should have a clear idea of what you did by just reading the abstract. To
achieve this effect, avoid references to the main body of the report ("...The data in Figure 2
show that the entropy of the Universe is indeed increasing...."). Even though it appears
before the main body of the paper, the abstract is the last part of the report to be written.
As a summary, the abstract should contain no insights and conclusions that are not developed in
the main body of the report.

         INTRODUCTION. In this section, you are to provide the reader with brief
background information on the system that you studied. More importantly, you should state
clearly the purpose of the experiment. This is the first section where literature citations may be
necessary.
         The Introduction is a good place to define reactions, equations, abbreviations, and terms
that will be used throughout the report. Again, avoid jargon specific to handouts because they
would not be understood by a reader who is not taking the course.

         EXPERIMENTAL SECTION. You should include a detailed account of your
experimental procedure; that is, what you did in the laboratory and how you did it. Observations
are also important. For example, if a reaction began to heat up upon addition of a reagent, then
report the observation.
         If you performed a procedure exactly as described in a handout or in the literature, then
you need only provide the reference. Any deviation from a given procedure must be described in
detail. The assumption is that any procedure for which no literature reference is given is one that
you developed yourself. If you do not give proper credit, you are guilty of plagiarism. Do not be
afraid to credit the suggestions and ideas of your classmates. You will always gain - rather than
lose - respect by adhering to this policy.
         When describing a new or modified procedure, provide enough detail so that anyone with
background similar to yours can repeat the work without rediscovering what you have already
uncovered. Avoid outline format when describing your procedures. Be sure to include in
your text:
         • the supplier and purity of your reagents;
         • the volumes, masses, and moles of your reagents;
         • methods of sample preparation (e.g., anaerobic, low or high temperature, etc.);
         • manufacturer and model number of commercial instruments;
Chemistry 302                            General Remarks                                  page 10


        •   a block diagram and a brief description of the main components of any home-built
            instrumentation ;
        •   the mass, number of moles, percent yield, m.p. or b.p (where appropriate) of your
            products;
        •   the literature values of m.p. or b.p. for a product, if it has been prepared in the past
            by the same or a different method.

        RESULTS. This is the most important part of your report. Your results must be shown
succinctly and clearly, so that the reader can evaluate the quality of your work and the validity of
your conclusions. Here are a few suggestions to help you in this task:
    • Use figures (which may contain structures, graphs, spectra, schematic views of
        instrumentation, etc.) and tables whenever possible.
    • Tables and figures are to be numbered for reference in the discussion. They should be
        given titles and legends. The legend should identify the sample, method of detection, and
        experimental conditions (temperature, power, resolution, etc.). The axes of graphs and
        spectra should be labeled clearly, with the appropriate units.
    • You should describe in words the key features summarized in the figures and tables. If
        you have a negative result, it is unnecessary to go into great detail. Simply summarize
        failed attempts so that the reader will know what to avoid.
    • You should analyze spectral data in detail. Obviously, the tenor and depth of the analysis
        will depend on the type of data and the purpose of the experiment. We will give you
        specific guidance on this in the upcoming handouts.
    • Raw data should not be presented. Data are presented far more effectively after
        processing in tabular or graphical forms. But, you may ask, what are raw data?
        • Example: suppose that you obtained the absorption spectra of a compound in twenty
             different solvents. The spectra are similar in shape, but the wavelengths for maximum
             absorption depend on the solvent. You decided to present your data by attaching all
             twenty spectra to the report, marking the position of the absorption maxima on each
             one. Consequently, the reader must leaf through twenty pages of data, only to extract
             one number from each page. The same data could be presented more effectively by
             showing a table of solvents used and the corresponding wavelengths for maximum
             absorption. The remaining spectra should be stored carefully in you laboratory
             notebook.
        • Example: suppose that you obtained two hundred pH readings for a titration of an
             aminoacid with a standard NaOH solution. Subsequently, you analyzed the data by a
             least squares method and obtained a list of calculated pH values that fit the
             experimental data. When presenting these data in your report, you should not
             provide a long list of experimental and calculated pH values versus volume of NaOH
             solution added. Instead, you should display the data in graphical form, as a titration
             curve, where both the experimental data points and calculated curve are displayed
             simultaneously.
    • If appropriate, include a full-blown sample calculation in the results section, showing the
        relevant equations. If the calculations were performed with a computer, then show the
Chemistry 302                           General Remarks                                  page 11


        pertinent equation and state what kind of hardware and software were used. Pay special
        attention to units.

    DISCUSSION. In the discussion section, you should elaborate on the meaning of your data,
explaining the behavior of your system with sensible scientific arguments that can be substantiated
by literature citations. You should also discuss sources of errors, low or high yields, suggest
improvements of experimental design, and answer questions posed in the lab handout. You may
also make hypotheses based on your results and propose experiments that can test the
hypotheses. Here are some additional guidelines:
    • It is possible to combine the Results and Discussion sections into a single section.
         Please ask one of us first before doing this.
    • Avoid rephrasing statements that were already made elsewhere in the report.
    • Avoid statements such as: "There is the possibility that bad laboratory technique or
         that a badly calibrated instrument led to errors". In a way, this is always implied;
         however, unless you can identify exactly how your technique or the instrument was
         flawed, the statement is not very useful because it is not specific. If indeed you can
         identify the flaw, then you should not submit a report on the experiment. Rather, you
         should repeat the experiment with an eye toward preventing the problem.
    • Avoid "fillers" like "I learned a lot of chemistry from this experiment" or "This was
         the experiment from hell". We will provide other vehicles for your praise and
         dissatisfaction: course evaluations!

    CONCLUSIONS. After interpreting your results, you will reach certain conclusions about
your experiment. In many cases, these conclusions were already included in the Discussion
section. If you wish, you may state them in a separate Conclusions section. Avoid repeating
yourself, though!

   ACKNOWLEDGMENTS. You should acknowledge minor contributions to experimental
work or data interpretation, as required by the Honor Code.

     REFERENCES. The section on Honor Code requirements states clearly our policy on
literature citations. Consult the instructor if in doubt as to what requires a citation.
         The References section (also referred to as the Literature Cited section in some
journals) is a very important part of your report. Among other things, references show the reader
that you have studied the literature and have found precedents for your arguments there. Also, it
makes people very mad when they are not cited for their work!
         Let us begin by discussing the differences between bibliography, literature citations, and
footnotes. In scientific papers, only the latter two are to be used.
         Researchers in the Humanities and the Social Sciences end their papers or books with a
bibliography: a list of their sources of information. Throughout the work, footnotes point to
specific chapters or pages of items listed in the bibliography, from which information was
extracted. Footnotes are also used to elaborate on a point developed in the text. This is not
how referencing is done in scientific papers.
Chemistry 302                            General Remarks                                  page 12


        Each scientific journal handles references in slightly different ways. One common link in
all of the accepted formats is the absence of the combined use of bibliographies and
footnotes. We will follow the style proposed by the editorial board of the scientific journal
Journal of the American Chemical Society. The ACS Style Guide is another source of
information on this subject.
        A reference is a journal article, a chapter in a book, or even an entire book. Each
reference is given a number; the numbering reflects the order of appearance of the reference in the
text. Every time you feel that a statement must be referenced, you should follow it with the
appropriate reference number in parentheses. For example,

        The rate of electron transfer between Ru(II) tris(bipyridyl) and Fe(III) in 0.1
        N HCl was obtained by the time-resolved fluorescence method of Lind et al.
        (1). These rates agreed to within 1.0 % with those obtained by flash
        photolysis studies (2).

         Here, a paper by Lind et al., is used as a reference for the experimental procedure. This
paper is the first reference of the report, so that it carries the number 1. Subsequent citations
carry different numbers.
         If you cite the same paper several times in your report, you should use the same reference
number for that paper. For example:

        The rate of electron transfer between Ru(II) tris(bipyridyl) and Fe(III) in 0.1
        N HCl was obtained by the time-resolved fluorescence method of Lind et al.
        (1). These rates agreed to within 1.0 % with those obtained by flash
        photolysis studies (2). Thus, our studies confirm the accuracy of the
        fluorescence technique, which was not assessed previously by Lind and
        coworkers (1).

         It is not necessary to point to a specific point of the article or book chapter when
referencing it. For example, you want to reference two rate constants from an article by Curie
and Herzberg. The first number appeared on page 543 and the second on page 567. Instead of
using two distinct reference numbers for this article, one for each page number where the
information is found, you should reference the entire article both times, thus using only one
reference number.
         At the end of the report, a separate section, entitled References or Literature Cited, will
list the references in increasing numerical order. You should give the reader unambiguous
information about the cited work so that it can be found easily. A journal article should be
referenced as follows:

        Yang, Y.-M.; Fales, H.M.; Pannell, L.K. Anal. Chem. 1985, 57, 1771-1772.
Chemistry 302                            General Remarks                                    page 13


         The names of the authors (last name first, then initials) are followed by the abbreviated
name of the journal, the year of publication, the volume number, and the page numbers of the
article.
         An article appearing in a book edited by a second party is referenced as:

        Schwartz, H.; Schiebel, H.M. in Chemistry of the Peroxides; Patai, S., Ed.;
        Wiley: Chichester, U.K., 1983; pp. 105-127.

        The names of the authors are followed by the book title, the editor's name, the name and
location of the publisher, the year of publication, and the page numbers.
        A chapter in a textbook or monograph would be referenced as in the following two
examples:

        Voet, D.; Voet, J.G. Biochemistry; Wiley: New York, 1990; Chapter 20.

        de Paula, J.C. Chymotrypsin: Catalytic Efficiency and Mechanism of Action;
        Haverford College: 1999.

       Scientific articles do use footnotes occasionally. They are reserved for parenthetic
statements that explain further a point brought up in the text. By separating a statement from the
main body of the text, the author can prevent disruption of the flow of logic. Most journals, such
as Journal of the American Chemical Society, treat footnotes and references equally, listing
them together at the end of the article.
       Please do not hesitate to ask questions about reference formats if the discussion above
seems nebulous. We are here to help! Have fun and good luck!

								
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