Results of careful laboratory work are not useful unless they can be presented in a clear, concise manner to others for comment and evaluation. Such presentations are usually in the form of a scientific paper published in a reputable scientific journal. Scientific communications have many things in common, which leads to a rather standard style of writing that allow the results and meaning of experimentation to be quickly grasped by the reader.
Scientists do not expect to read attractive, stimulating prose to obtain information from technical scientific papers as seen in lab report example biology. The experimental design, results and explanation of results are what are attractive and stimulating not the cleverness of the prose. The following discussion should be useful in helping you prepare your laboratory reports, which are scientific reports.
Read it carefully before beginning your reports. Your laboratory instructor may make additional comments. The specific format of a scientific paper varies among journals. However, the format presented below is the most commonly used. It is the format you should use in how to write a lab report.
Part I: Format of a Scientific Report
The scientific report will be composed of seven sections. Each section will have a heading and the text, figures or graph of that section follows immediately. The order of the sections is: title, abstract, introduction, methods, results, discussion and literature cited.
(1) Title Section
Create a title that briefly conveys to the reader the purpose of the paper. The title of your report must be informative. Many readers scan journal article titles, and the decision whether or not to pursue an article is based on the information in the title. Generally, this information includes: primary factor(s) manipulated or studied; outcome of manipulation (the response or effects); and organism studied, if relevant. Lab report example biology of an informative title would be: “The Effect of Varying Serotonin Concentrations on Calcium Release at Synaptic Membrane in Motoneurons of Aplysia.“
(2) Abstract Section
The Abstract should be an autonomous summary of the entire report. It serves to help readers determine how relevant the report is to their own interests. This section is brief, only one or two paragraphs (200-300 words), in which the author indicates what was done, the reasoning behind it, the results and the conclusions. The scientific report can be summarized into an abstract by creating four types of statements: purpose statements (however once should never literally write “the purpose of this experiment is…” or any derivation there of), that are general statements describing the importance and/or goals of the research; methods statements that explain what was done and how it was done; results statements that describe what information or data was acquired; and discussion/conclusion statements that explain what the information or data probably means and what conclusions are drawn. Only the most important aspects of the report should make it to the abstract.
(3) Introduction Section
This section should indicate why the study was done and give the reader sufficient background to understand the report or paper. The “why” of the study usually includes historical information that leads to your study and the significance of the study to a specific discipline (such as developmental neurobiology) to which the study belongs. The reader, after perusing the introduction, should know precisely the importance of the problem being addresses. You should write about the questions you will be answering in this experiment. Note: any historical background (that is, previous studies) must be properly cited. This section must include 4 peer reviewed outside sources (outside of lab book and text book), of which 2 should be primary literature on how to write a lab report for chemistry.
(4) Methods Section
A reader can evaluate the results of your study only if he or she understands the experimental design, the materials used and the reasoning behind them. Thus, it is important to carefully outline procedures and techniques used. Complicated procedures might be graphically outlined. Besides procedures, this section should include models or equipment used (this should not be written like a laundry list of materials), source of chemicals (if relevant), numbers and types of organisms used, including sex and strain sample sizes, number of times experimental procedure was performed, and other pertinent factors. Please note: There should NEVER be a list of materials in this or any section in lab report example chemistry.
(5) Results Section
It is crucial that the outcomes of experiments are carefully organized and clearly presented. This is best accomplished by presenting data in clearly labeled graphs and tables. What the tables and/ or graphs are meant to indicate should be clear without reference to text. However, references to each graph and table MUST be made in the text of the Results section. Graphs and tables should be numbered in the order in which they are mentioned in the text; that is, tables should be labeled as consecutive series (Table 1, Table 2, etc.). The text should also summarize information presented in tables and/or graphs that will be pertinent to the discussion section. You cannot turn in a lab report with a results section that does not have associated text explaining the incorporated figures how to write a lab report for biology.
(6) Discussion Section
Do you know how to write a discussion in a report? In brief, the Discussion section is where results are analyzed and conclusions are drawn. The significance and interpretation of the study should be explained in this section. Specific points made in the Results section should be discussed in light of previous studies and hypotheses. Often, new hypotheses are put forth, based on the experimental outcome. The most important part of the Discussion section is establishing what the results indicate, both for the ongoing study and for future studies. how to write a lab report physics. Were the questions you included in the Introduction section, answered by this study? If not, how could the study be redesigned? Some questions that can be answered in interpreting the results in the Discussions section are: Why are these results the same as (or different from) previously published studies (or my peers)? What parameters of the experimental design were important in the expected (or unexpected) results? Are some of the results due to artifacts? How do you know? How might the experimental design be altered to diminish artifacts?
(7) Literature Cited Section
This section includes the alphabetical listing of all sources of fact or theory mentioned in your paper that were not generated by you. This will primarily include research articles, but may include review articles and texts as well. The citations should be written like the ones illustrated below.
Hints for Scientific Writing:
Note: Problems arise in writing scientific papers because of specific aims of scientific writing: to be clear, concise, unambiguous, and accurate. Due to the space restrictions in journals and time limitations of your instructor, every word must help to convey the required information. The report as a whole should be objective and self-explanatory. The following seven recommendations should help you with your writing for this scientific report.
- Avoid wordiness. Eliminate redundancies.
- Write in the past tense. You can use the present tense for conjectures in the discussion section.
- Do not use footnotes.
- Be sure that there is text in the Results section. Also, make sure that each graph and/or table is referred to and that reference is not made to nonexistent tables or graphs.
- Check that each section contains the proper information; for example, do not put results in the Methods section.
- Check that each Literature Cited item is in the text and that each citation in the text appears in the Literature Cited section. This includes proper in-text citations.
- Never write “My hypothesis is…”, “The purpose of this experiment is..”, “My predictions are…”
Part II: Guidelines for BSC 1010 Lab Reports
A) General Rules:
- If you are not present in lab you cannot turn-in a lab report for that lab.
- You need to be an active participant in all labs which contain experiments for the lab report. You will clean up your bench area before you leave the lab.
- You will be present (or have an excused absence) for the lab. You will need to contact your instructor to discuss what your options are for making up/collecting the data for the lab report, if you miss.
- You will turn in your lab report in its entirety. Turning in one or more components or sections of the lab report after the due date and time will make the entire lab report late.
- This lab report must be your own work (no plagiarism). Content used from references needs to be cited.
- It is your responsibility to turn your lab report into your instructor at the beginning of the lab session. The report will be late if it is turned in after your instructor has left the lab. A late lab report will lose 10% of the total possible score every day it is late. The 24 hours counts from the beginning of your lab time.
- It is YOUR responsibility to turn in the lab report on the day that it is due. The due dates have been posted and well known.
B) Format regulations:
- double spaced
- 10 font, Times New Roman (let’s save paper)
- 1 inch margins
- pages numbered
(1) Title Page/format:
This page should contain your name, signature, Panther ID, lab partner(s) name(s), title and lab section. The report should contain seven clearly identified sections: title, abstract, introduction, methods, results, discussion, and literature cited /reference section. The complete report is to be typed, on 8.5″ x 11″ white paper, font size is reasonable and formatted to your instructor’s specific requirements. The overall presentation/grammar/spelling will be evaluated. Before you turn in your final version, use the spell check function and reread your report.
This section should be between 200 and 300 words in length. This section should contain a clear summary of what was demonstrated, how each part of the lab was carried out and how conclusions were reached. This section should contain one or two purpose statements (without saying “The purpose of this experiment is…”), a complete summary of each experiment (method statements) in a few sentences, and brief, accurate explanations of the results. The final sentences should be the concluding statements.
This section contains the basic background information for the lab report. Be sure to comment on what is the significance of this study and its relation to the larger field. Give an example of why the study is significant. Your hypothesis is used to make the prediction(s). The predictions are based on the background information that was gathered. You should have a clear statement of the reason for performing the lab along with including the rationale for each technique used.
- What was the purpose of each experiment? For each experiment, include questions that will be answered and the expected predictions of the results for each question. Try to include a hypothesis. (without saying “My predictions are…” or “My hypothesis is…”)
- This section should be about 450-700 words long and smoothly flow from one topic to the next.
- This section is no more than 300-450 words and is a narrative
- Include a brief description of how each experiment was performed. There should be enough detail so the reader (experienced researcher) could repeat the experiment.
- You should explain the procedural steps taken (summarize) and not create a duplicate of the instructions from the lab manual.
- No list of materials is permitted.
- All graphs and tables should be your own work! Graphs and tables should not be identical to anyone else’s in the lab, including your lab partner’s.
- The number of pages will vary depending on the number of graphs, tables and other illustrations needed. Make sure everything has a Figure number or Table number.
- Also include a concise detailed description, which clearly summarizes the graph or table. Include comments about the results for each experiment and control. This text is a verbal description of what the table/graph/picture is illustrating (enough detail to be on its own).
- The text should be around 250-450 words long
- This section should be approximately 500-800 words long.
- This section should include a clear discussion in relation to each hypothesis and to what is known about the topic (reported by other researchers).
- Include a summary of your results and explain how you interpreted your results (why did things turn out the way they did?). Be sure to refer to the specific illustration whenever discussing the results.
- Remember nothing is ever proven. So the results either support or refute your original hypothesis.
- Also, explain why the control and experiment were what you expected or were not what you expected.
- Comments should also be made about problems and/or improvements for the next time.
- Here is where you are essentially asking “why” everything/anything happened during the experiment.
(7) Literature Cited / References:
- You should include at least six references .
- YOU MUST HAVE IN-TEXT CITATIONS!!!
- Any citation in the body of the report is put at the end of a sentence and should be done like this (Author’s last name, year). Do not write all of the author’s names for in-text citations. If there is only one author, then write the name of the principle author. If there are two authors, then you must write both names and if there are multiple authors write et al. after the name of the principle author (Yes in italics- it’s in Latin).Example: (Simms et al., 2010)
- Anything that you or other biology students reading your report would not know off the top of your head, needs to have a citation at the end of the sentence. This includes anything looked up and used. This is especially important in the introduction.
- Your textbook can be cited as the source of basic biological information related to the topic of the report.
- Many sentences in the introduction will have citations at the end, so make sure the content flows smoothly from beginning to end. Try not to have every sentence with a citation. Use connecting sentences and your own ideas or summaries of the experiments where possible. Remember to put the in-text citation before the final punctuation of the sentence.
- You must include 4 peer reviewed outside sources (outside of lab book and text book), of which 2 should be primary literature.
- No website references or any encyclopedia references are allowed.
The Lab Report: (Your lab TA may specify slight modifications to the format below).
1.) Title Page: The title page is usually centered top and bottom as well as left and right and should contain the title of the lab (don’t just write “Investigation #”), the names of each of the group members, the date the lab was concluded, TA name, and section of the lab. Ex: CHM 113EA
2.) Introduction: The introduction of a scientific report is meant to give an overview of the entire experiment without delving into the precise details of your experimental method or results. Your introduction should be concise (at most two brief paragraphs) where you state:
- The experimental goals
- A short background (This includes the chemical theory, concept, method, and mathematical or chemical equations that are central to the investigation.). Do not show detailed calculations used for calculating results but can include general equations, e.g. the Ideal Gas Law, PV = nRT, in describing theory.
- Your general approach to solving the question or problem
- Do Not:
- Copy goals from the lab manual word for word
- Give detailed methods used in the lab
- Describe or report final results
The goal was to determine the identities of several unknown samples of metal provided. Metals possess a wide range of chemical and physical properties; by measuring a few such properties and comparing them to tables of known values the identity of each of the unknown samples were obtained. Most metals have a characteristic density, ductility and conductivity. In some cases luster and color are also distinct enough to aid identification. By measuring multiple properties, a sample was identified if two or more properties overlapped. Given the resources available it was decided to observe and measure the color, density and conductivity of the unknown samples.
The lab manual told us to measure the color, density and
conductivity of the five metal samples we were given and determine which metals
they were. We weighed the samples on the
balance then calculated their volumes using a ruler and geometry. One sample was reddish orange, two were dark
gray, and the other two were a dull silver.
We used the Handbook of Chemistry and Physics to look up the densities,
conductivities and colors of common metals and compared them with our
data. Based on densities our samples
could have been lead, copper, tin, iron, aluminum or titanium. Comparing this list against the list of
conductivities we determined our sample was not tin which meant our samples
were lead, copper, iron, aluminum and titanium.
If you look at the examples above you’ll notice that both sample introductions provide, qualitatively, the same information. Both explain: the goal of the experiment, which chemical principles were being studied and the experimental route taken. However, the example on the left manages to provide an introduction to the experiment without going into specific experimental details that are best left for the Materials & Methods section or the results and lines of analytical reasoning that are the domain of the Results & Discussion. The example on the left was in the correct tense and also does a better job of introducing the intent of the experiment whereas the example on the right tells the reader the authors were following instructions in a book. Also note the example on the right (second part of last sentence, “….we determined our sample was not tin….”) gives the results – save this for the discussion section. A well-written Introduction must find a balance between having too much and too little information.
3.) Materials & Methods (sometimes called “Experimental”): This is by far the most straightforward section in the body of your lab report. This section is the step-by-step account of the experimental procedures you followed. Start this section with an itemized list of any specialty glassware/equipment used and a list of known chemicals used. The procedure should not be copied from your lab manual if one is given. Write about what you actually did stating specifics, like volumes, concentrations, and names of specific chemicals used . ALWAYS: 3rd person, past tense, passive voice! Example: A total of 1.25g (0.0214 mol) NaCl was dissolved in 300 mL distilled water to make a 0.0713 M solution. Remember to write in complete sentences. When writing numbers, put a zero in front of decimal places and use the correct number of significant figures. Your procedural description should not be a five-page essay but enough detail should be given such that someone else could read this section and duplicate what you did in the lab. IMPORTANT: Do not report your data in this section; your data are reported in Results.
4.) Results: The Results section is where all data and sample calculations should be presented. Many data are individual measurements, meaning that in the body of your results you simply need to highlight it and possibly other single measurements.
Laboratory Temperature = 23.5˚C ± 0.5˚C
If there are larger sets of related data you should present them in a table with a proper number, title and legend.
Table 1: Sample Mass & Volume
|Sample #||Mass (g)||Volume (cm3)|
|1||35.603±0.002 g||4.1 ± 1 cm3|
|2||25.782±0.002 g||8.0 ± 1 cm3|
|3||47.981±0.002 g||12 ± 1 cm3|
|4||19.826±0.002 g||15 ± 1 cm3|
|5||27.110±0.002 g||3.6 ± 1 cm3|
If you note above, the data point and table (all with fabricated numbers) are presented in and around the body of the text. This is the pattern you should follow when writing your own Results section; describe the measurement/s taken briefly, then present the data. You do not need to describe the full experimental procedure you followed because that should have been accomplished in the Materials & Methods section. However, you do need to refer back to that procedure to provide the proper context for your data. Without any text to provide the proper context most data appear as just numbers on a page, devoid of their full import.
In general, the process of
performing calculations on the data collected during an experiment to obtain
the final results is termed data processing.
In some experiments the calculations are relatively simple while in
others the results are only obtained after extensive data processing. As with raw data, however, sample
calculations need to be presented in the body of your Results section to
provide the proper context to the numbers.
35.603 / 4.1 = 3.237
25.782 / 8.0 = 3.473
47.981 / 12 = 3.998
19.826 / 15 = 1.322
27.110 / 3.6 = 9.037 g/cm3
Density bears the units of g/cm3, which may be determined by dividing the sample’s mass by its volume. For unknown sample #1:
/ 4.1cm3 = 8.7 g/cm
Presented above are two example of what sample calculations might look like. In the example on the left there are only units on the final results and with no textual reference to put the results in context; it is left up to the reader to realize they are your density calculations. In this example it is difficult to understand the example on the left without context, and it’s not hard to imagine the calculations quickly growing beyond simple boundaries and becoming too complex for even an attentive readers to follow. In the example on the right, however, the calculation is put in context, all the numbers bear their appropriate units and only one, sample calculation is presented. The full array of sample densities would be best presented in a data table such as Table 1, or in a new table altogether.
Finally, some data and results are best presented graphically and since lab reports must be typed it will be helpful to become acquainted with a program capable of graphing your results. MS Excel and some other programs offer the ability to plot data and perform linear regressions.
- When writing Chemical Equations, include phase symbols and charges.
- Number equations so that they can be referred to elsewhere in the report.
- Use Data Tables whenever you can.
- Label all data tables/graphs/charts with numbers and descriptions.
- Show statistical error calculations when appropriate.
- Use units for all numbers.
- Do not explain your results.
- Do not show every calculation of one type.
- Do not regurgitate the Experimental section.
- Do not break up tables on more than one page.
5.) Discussion: NOTE: Sometimes Results and Discussion are combined
into 1 section but it should then be specifically titled “Results &
Discussion”. The Discussion is by
far the most important section of a lab report.
In it the experimental results are analyzed and put into the context of
the chemistry being studied. The theory
from the Introduction, the procedures from Materials and Methods and data from
Results are all drawn together to answer the question first posed to the
researchers. Refer to the tables and graphs presented in the Results section! (ex:
‘As can be seen in Figure 2…’ or ‘From Table 3 it can be determined that…’) It
is critical that the Discussion section lead the reader through the line of
reasoning the authors used to draw their conclusions from their measured
Color and density are intensive and characteristic properties of metals. The color and density of several metal samples were obtained and compared to tables of known values. Since several metals share similar colors and densities their correspondence with two properties were used to uniquely identify each sample. Sample #1 possessed the typical bronze color associated with copper and the measured density was 8.68 g/cm3, close to the known density of copper of 8.92 g/cm3. This led to the conclusion that sample #1 was copper. There was significant error involved in measuring each sample’s volume, leading to a 25% uncertainty in the density. Despite this, the method followed was accurate for the purpose of determining the identity of sample #1.
density of sample #1 was measured, and by looking at the color, it was determined
to be copper. There was human error in
making this decision since the color was determined by visual inspection. Color and density are important properties of
metals and let you positively identify metal samples.
The example on the left is clearly superior; it addresses the chemical principles being studied in the context of the problem set before the researchers then leads the reader through the line of reasoning used to draw conclusions at the end. It also addresses valid sources of error and their probable effect on the outcome of the experiment. The example on the right is too short, lacks a clear line of reasoning and blames the experimental error on the researchers’ technique simply because they lack a more valid source of error. A full discussion, of course, would address all samples studied and sources of error in a similar fashion. If possible always compare your results to the theoretical or known values, especially if your values deviate from what you expected or if you believe your expectations were somehow incorrect.
6.) Conclusion: NOTE: Sometimes Discussion and Conclusion are combined into 1 section but it should then be specifically titled “Discussion & Conclusion”. The Conclusion in many ways resembles the Introduction. The Introduction is an overview of the entire experiment, including the goals and chemical principles to be investigated while the Conclusion is an overview of the completed experiment where you discuss whether you achieved the goals and whether your approach to the experiment was successful. The Conclusion should not repeat the points presented in the Results & Discussion, but rather tie those points together with those elements of the Introduction just mentioned. In summary, the conclusion is a very short paragraph, generally an interpretative summary, drawing conclusions about the experiment itself. How do the results relate to the initial goals of the experiment? Can alternate conclusions/explanations be drawn? If the problem wasn’t solved completely, do you have any suggestions how the experiment could be improved/refined?
In this lab, the identities of several unknown metal samples were determined. Using the properties of metals, each sample’s color was observed, and its density and conductivity measured. Upon analysis it was determined that density alone was insufficient to identify each sample and it was required to cross reference density with conductivity and color to positively identify each sample. Overall, the approach was a successful application of density and conductivity to identification of unknown metals.
7.) References: This is the final section in your lab report and should contain the bibliographic entries of any and all reference materials used in the writing of your lab report. Examples include, but are not limited to: your lab manual, textbook and reference materials found online or in the LRC.
*****This guide is meant to supplement the general guidelines for writing lab reports presented on pages 4 & 5 of the CHM 101, 113, 114 and 116 lab manual. As noted, these are only guidelines; but when it comes time for your lab reports to be graded, following these guidelines may make the difference between getting a ten, a nine, or having to rewrite it. When in doubt, ask your laboratory TA. *****
- DON’T FORGET TO ANSWER THE QUESTIONS POSED BY THE LAB MANUAL!!
- Use proper sub and super scripts: It is Na3PO4 not NA3PO4 or Ca2+ not Ca2+
- Chemical names are not capitalized.