University of Minnesota DuluthDepartment of Chemical Engineering

ChE 3211 Chemical Engineering Laboratory Drs. Davis and Wang

111Equation Chapter 1 Section 1

Laboratory Report Writing Style GuideA major engineering company gave these instructions to engineers in training:

“It is not sufficient that a report be capable of being understood; it is required that a report be incapable of being misunderstood.”

Many engineers and scientists find report writing difficult. However, chemical engineering graduates in their first industrial job will quickly realize the importance of good writing and technical communication. The laboratory courses provide students with the opportunity to develop their writing and speaking skills.All forms of communication utilized in this laboratory class are expected to follow grammatical rules and a formal, technical writing style. A review of the following sources is recommended:

"Engineering Communication" by H. Hart, 2nd Ed., Prentice-Hall, 2008.

"The Elements of Style" by Strunk, Jr. and White, 5th Ed., MacMillan, 2009.

“The ACS Style Guide” by Coghill and Garson, 3rd Ed., American Chemical Society, 2006.

Comp 3130 NotesSome general principles of technical writing follow. However, this style guide is not a complete overview of technical writing style. Students should consider other examples of technical writing, such as engineering textbooks and scientific or engineering journals, as they develop their technical writing skills.Technical writing is dramatically different from creative writing in at least two ways. First, technical writing is concise. Metaphors are kept to a minimum. Information is presented in the form of equations, figures, charts, graphs, and tables, in addition to written descriptions. Second, technical writing arrives quickly at the results and conclusions. The plot usually does not contain a mystery or surprise ending.Since technical writing involves technical language, it is important that sentences do not run long. Readers may have difficulty assimilating the material written in long, complex sentences. Consider the Fog Index as a test for proper sentence length.

FI = 0.4(words per sentence + polysyllabic words per sentence) 22\* MERGEFORMAT ()

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Table I gives the range of FI for different print media. Generally, a FI < 10 is desirable.

Table I. Fog Index (FI) scale.Written Media FINewspapers 5Magazines (e.g. Time, Newsweek) 6-7Novels 6-7Literary Magazines (e.g. Atlantic Monthly) 8-10

Consider the following sentence composed by J. Willard Gibbs, communicating his ideas on heterogeneous thermodynamics.

“Which are capable of only one kind of action upon external systems, viz., the performance of mechanical work, the function which expresses the capability of the system for this kind of action also plays the leading part in the theory of equilibrium being that the variation of this function shall vanish, so in a thermodynamic system, (such as all material systems actually are,) which is capable of two different kinds of action upon external systems, the two functions which express the two fold capabilities of the system afford an almost equally simple criterion of equilibrium.”1 (FI = 55)

Contrast Gibb’s sentence with Caesar’s message:

“I came. I saw. I conquered.” (FI = 1)

PersonUse person to your advantage. The standard for technical writing has been third-person. Recently, there has been a shift to first-person in the technical literature. Either form is acceptable today. Consider the following examples.

Third person:

“Implementing this proposal will cost the company $5 MM per year.”

First person:

“Our proposal will save the company $5 MM per year.”

Notice that the third-person style deflects the negative conclusion away from the authors, while the first-person connects the authors with the positive conclusion.

VoiceUse active, action oriented voice wherever possible. A passive voice tends to produce wordy sentences (recall the Fog Index) that focus on the action instead of the subject. Try to eliminate conjugations of the verb “to be” in your sentence construction to promote the active voice. The verb "to be" is the most irregular verb in English. The verb “to be” is conjugated in Table II.

Consider the following sentences:

The temperature is measured by a digital thermocouple.

1 Gibbs, J.W., The Scientific Papers of J. Willard Gibbs, Longmans Green and Co., 1906, p. 55.

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A digital thermocouple measured the temperature.

The second sentence conveys action and is more concise. It may take some time to learn to integrate action into your sentences, but soon it will be habit and your technical writing will benefit from it.

Table II. Grammatical conjugation of the verb “to be.”Infinitive: bePresent Participle beingPast Participle beenFuture Infinitive will bePresent Progressive am being

is beingare being

Past Progressive was beingwere being

Person, Number Present Past1st, singular I am was2nd, singular you are were3rd, singular he/she/it is was1st, plural we are were2nd, plural you are were3rd, plural they are were

TenseBe careful to use tense to properly describe the subject of the report, not the report itself. Use past tense when writing about the work completed to generate the report. Write about the results of the work in present tense. Limit future tense when writing about future work or plans. Do not fall into the trap of using past, present, or future tense in reference to sections of the report. For example, the following sentence type is not acceptable.

“The design equation will be derived in Appendix B.”

Instead, use present tense:

“The derivation of the design equation is presented in Appendix B.”

And better yet:

“Appendix B presents the derivation of the design equation.”

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Benjamin Franklin said, “Either write things worth reading or do things worth the writing.” You will be required to produce two types of written reports: a full length, or formal report, and a memo report, documenting your laboratory work.Guidelines for the full reportSample ReportA Sample Report for a very simple experiment is provided on the course Moodle site. Its purpose is to illustrate how a report should be organized and to indicate the kind of material it should contain. This example is not meant to provide a rigid outline; the content of the report will depend upon the context and your judgment. General comments now follow.Letter of TransmittalA standard transmittal letter should be included with the report. The letter should briefly describe the origins of the report and what the reader should expect to find in the report. Both authors should sign the letter. Do not bind the letter with the report. Put the letter inside the front cover. CoverFormal reports must be bound with a GBC type of binding and a card stock cover. The report's title and author's name must be printed on the cover. Binding a report gives a sense of completion and formality to the writing experience.FormatReports should be prepared on letter-size paper (8.5 by 11 in) with the following layout:

Right margin – 1 inch Left margin – 1.25 inches (to allow room for the binding) Top & Bottom margins – 1 inch Line spacing – 1.5 inches.

You are free to use proportional fonts, Times New Roman is preferred. You should avoid the use of a type style that is san serif, such as Arial, for scientific writing. The point size should be 12 point. Titles and headings may be larger, san serif type, such as 14 or 18 point Arial typeface. In the interest of having Word automatically create a table of contents, you may want to create your own style set. For example:

Heading 1 (Arial, bold, 12pt) Heading 2 (Times New Roman, underlined, 12pt) Normal (Times New Roman, 12pt)

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Caption (Arial, bold, 10pt).It is best to create a style set and determine paragraph spacing at the beginning of the writing process. Your style must be consistent throughout the entire document.It is not essential to start each document section on a new page.Do not write information directly out of laboratory handouts or references. Paraphrase or summarize it, and cite the source. TitleThe title of the report should be concise and definitive. The first letter of each word in the title should be capitalized. Center the title between the margins. The title page should include the name of the recipient, the names of the team in alphabetical order by last name, and the date of submission.

AbstractThe purpose of the abstract is to give a clear indication of the objective, scope, and results so that readers may determine whether the full text will be of particular interest to them. The abstract text should be organized to include the following categories in the order noted:

Background. Begin with explanatory text that discusses the background.

Method of Approach. Next, describe the method of approach.

Results. Results are provided at this point in the abstract.

Conclusions. Concluding remarks are stated at the end of the abstract text.

This should contain about 400 words or less. The important result must be given with its associated estimates of uncertainty. If the experiment generates many data, the range of values should be given instead. There should be no references cited in the abstract. Additional notes on the abstract are available on the course Moodle site.Table of ContentsThis should include all the Sections, Appendices, and their page numbers. If you have correctly used a style set, Word can automatically generate the table. If you choose to generate your own Table of Contents, the page numbers must be set at the right margin with a right tab and a "…" leader. List of Figures and List of TablesFollowing the Table of Contents is the List of Figures and the List of Tables. Each item in the Lists should include its page number as in the Table of Contents. Word can also automatically generate these Lists if the figure and table captions have been properly formatted. Introduction

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This should state the purpose of the experiment and give a very brief outline of the necessary theory, which is often done by citing pertinent equations. (In the Sample Report, the theory is simple.) A very short description of the experimental method with mention of any special apparatus should be included. A picture or schematic of the experiment is required. The relevance, general importance, or an application of the experiment should be described in one or two sentences.TheoryA condensed derivation of the equations to be used may be given here. An equation may be part of a complete sentence. Number all equations that occupy separate lines consecutively throughout the entire report and refer to them by number. Equations that occupy separate lines should be centered between the margins. The equation number should be set at the right margin by a right tab stop. All symbols should be defined at the point where they first appear. Symbols should also be defined in a notation section; this is especially important if there are many symbols. A condensed tabulation of essential data is often useful. It is unnecessary and undesirable to present all computations in the report; however, a typical sample calculation should be given in the appendix to show how the calculations were done. Appendices may be used to present detailed derivations, and long calculations. For a long calculation it is desirable to tabulate all of the important intermediate results; this should be done in an Appendix.A theory is not tested in the Sample Report. In cases where theories are tested, the expected results should be discussed.Experimental MethodsThis section briefly describes the experimental steps and merely cites the appropriate references that describe the full details of the experimental procedure. Reference will usually be made to the laboratory handout. A description of experimental procedures should be given only for those features not described in or differing from that described in the reference. A simple sketch of the apparatus is appropriate.Criteria for equilibrium or steady state should be given when appropriate. A statement of the number of runs made and the conditions under which they were carried out (concentration, temperature, pressure, etc.) should always be included at the end of this section. This helps the reader to understand the presentation of the results.Results

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Here you should draw the attention of the reader to the location of the raw data, intermediate results, and error calculations; these items will probably be in the Appendices. However, a graph or table of the final results is required in the Results section. The presentation of results in graphs is preferred to tables where possible. Error bars or uncertainty information must be included in graphs and tables. The final results should be presented here or at the beginning of the next section.Discussion (May be combined with Results when these sections are short).This is the most flexible section of the entire report. The final results of the experiment should be clearly presented if they have not been done so in the Results section. Think critically about your results. Are they reasonable? A comparison between these results and theoretical values or experimental values from the literature should be made. Error limits are important for such discussions. Comments should be made on any discrepancies. For example, comment on possible systematic errors and the relative importance of various sources of random error. Perhaps a brief suggestion may be made for an improvement in the experimental method.Conclusions & RecommendationsSummarize the results and critical conclusions. Make any recommendations for improvement or future work.NomenclatureList all symbols with definitions and typical units. List symbols alphabetically. Subscripts or Greek symbols may follow in a separate listing.

ReferencesMake sure that each one is cited at least once in the body of the report. References cited by the authors' name and date is the most straight-forward method. Examples: "as demonstrated (Allan, 1996a, 1996b, 1999; Allan and Jones, 1995). Kramer et al. (2000) have recently shown …"

Alternatively references should be numbered in the order of appearance in the text. Examples: "as demonstrated [1, 2, 3]. Kramer et al. [4] have recently shown …"References should be given in alphabetical order unless a numbered reference system has been used. In such a case, the references are given by number in the order of appearance in the text.Appendices

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Make sure that each appendix is cited at least once in the body of the report. Appendices may be used for any material that would "clutter" the body of the report. The appendices must include at least the following items: work plan, original data sheets, sample calculations, uncertainty analysis, and a summary of safety information, such as information from material safety data sheets of hazardous materials, if any.FiguresCaptions are placed below the figure. The figure caption must be a good description of the figure. Axes of graphs should be clearly labeled with the variable and its units. The variable is best described in words along with its symbol. Data and theoretical curves should be clearly distinguished by using a legend. Each graph and illustration should be numbered sequentially with an Arabic numeral accompanied with a title. If using a spreadsheet, make sure you plot the type of graph you want (usually an "XY" graph). Your reports must include a minimum of one figure of a schematic of the apparatus.

A figure legend is only needed when there is more than one set of information displayed. You may include the legend information in the figure caption, instead of in the graph. Be sure to use different symbols and line types to distinguish between data sets. For an example, please see the Graphing Guide on the Moodle site.

Tables

Each table should be numbered sequentially with a Roman numeral accompanied with a title. The title is placed above the table. The table caption must be a good description of the table. Conditions relating to each experiment should be given in a table’s footnotes. Column headings for numerical data should contain units (see below). Horizontal lines are often sufficient to format a table - look at how tables are formatted in a textbook. The value of a physical quantity is expressed as the product of a pure number and a unit, for example:

p = 1.013 × 105 Pawhich rearranges to

p/Pa =1.013 × 105 or p/(Pa ∙ 105) = 1.013.To avoid repetition of the unit symbol, it is common practice to tabulate data in the form of pure numbers. It follows that column headings should be dimensionless, e.g., p/Pa and not p(Pa). A column heading such as p(Pa) implies pressure multiplied by Pa, when one really means pressure divided by Pa. As an example of this notation, the data in Table III refer to the vapor pressure of acetone at various temperatures:

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Table III. Vapor pressure data for acetone (used in Antoine plot).

T/oC T/K p/(Pa ∙ 105)

103 K/T Log10(p/Pa)

40 313 0.561 3.195 4.74950 323 0.817 3.096 4.91260 333 1.155 3.003 5.06370 343 1.600 2.915 5.204

The same considerations apply to the labeling of graphs. It is clear when this convention is being used - the solidus (/) is always present.OtherWhen referring to tables, figures, and equations in the body of the report, the words "Table," "Figure," and "Equation" should start with a capital letter. For example, "The data are given in Table I and plotted in Figure 2."Presentation of EquationsAll equations (mathematical and chemical) must be numbered in the order of appearance in the report. Use standard mathematics notation for the presentation of equations. For example:

U =M [ (1+D )B−1D ]. (2)

Microsoft Word has an Equation Editor that may be used to generate equations in standard notation or formats.

Avoid equation formats used in computer software, such as Excel or BASIC.

U=M∗[((1+D)B−1)/ D] (3)

It is not clear how the exponent is intended in Equation 3.

Inline equations and units are presented horizontally, e.g.

W ∙m−2 ∙ K−1 instead of Wm2∙ K

.

Use a Spelling/Grammar Checker

But, be careful. Spell check, grammar check, and AutoCorrect often will make incorrect suggestions. Consider the following poem.

Ode to Spell Czech

Eye halve a spelling checker. It came with my pea sea.

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It plainly marquees four my revue miss steaks eye kin knot sea.Eye strike a key and type a word and weight four it to sayWeather eye am wrong oar write. It shows me strait a weigh.As soon as a mist ache is maid, it nose bee fore two longAnd eye can put the error rite. It’s rarely ever wrong.Eye have run this poem threw it, I am shore your pleased two no.Its letter perfect in it’s weigh. My checker tolled me sew.

Conclusion"Success in engineering and research depends as much upon the ability to present an idea convincingly as it does upon the ability to perform calculations and experiments." - T. O. Richards, General Motors Corporation.

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