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How to Write a Lab Report – with Example/Template

April 11, 2024

Perhaps you’re in the midst of your challenging AP chemistry class in high school, or perhaps college you’re enrolled in biology , chemistry , or physics at university. At some point, you will likely be asked to write a lab report. Sometimes, your teacher or professor will give you specific instructions for how to format and write your lab report, and if so, use that. In case you’re left to your own devices, here are some guidelines you might find useful. Continue reading for the main elements of a lab report, followed by a detailed description of the more writing-heavy parts (with a lab report example/lab report template). Lastly, we’ve included an outline that can help get you started.

What is a lab report?

A lab report is an overview of your experiment. Essentially, it explains what you did in the experiment and how it went. Most lab reports end up being 5-10 pages long (graphs or other images included), though the length depends on the experiment. Here are some brief explanations of the essential parts of a lab report:

Title : The title says, in the most straightforward way possible, what you did in the experiment. Often, the title looks something like, “Effects of ____ on _____.” Sometimes, a lab report also requires a title page, which includes your name (and the names of any lab partners), your instructor’s name, and the date of the experiment.

Abstract : This is a short description of key findings of the experiment so that a potential reader could get an idea of the experiment before even beginning.

Introduction : This is comprised of one or several paragraphs summarizing the purpose of the lab. The introduction usually includes the hypothesis, as well as some background information.

Lab Report Example (Continued)

Materials : Perhaps the simplest part of your lab report, this is where you list everything needed for the completion of your experiment.

Methods : This is where you describe your experimental procedure. The section provides necessary information for someone who would want to replicate your study. In paragraph form, write out your methods in chronological order, though avoid excessive detail.

Data : Here, you should document what happened in the experiment, step-by-step. This section often includes graphs and tables with data, as well as descriptions of patterns and trends. You do not need to interpret all of the data in this section, but you can describe trends or patterns, and state which findings are interesting and/or significant.

Discussion of results : This is the overview of your findings from the experiment, with an explanation of how they pertain to your hypothesis, as well as any anomalies or errors.

Conclusion : Your conclusion will sum up the results of your experiment, as well as their significance. Sometimes, conclusions also suggest future studies.

Sources : Often in APA style , you should list all texts that helped you with your experiment. Make sure to include course readings, outside sources, and other experiments that you may have used to design your own.

How to write the abstract

The abstract is the experiment stated “in a nutshell”: the procedure, results, and a few key words. The purpose of the academic abstract is to help a potential reader get an idea of the experiment so they can decide whether to read the full paper. So, make sure your abstract is as clear and direct as possible, and under 200 words (though word count varies).

When writing an abstract for a scientific lab report, we recommend covering the following points:

  • Background : Why was this experiment conducted?
  • Objectives : What problem is being addressed by this experiment?
  • Methods : How was the study designed and conducted?
  • Results : What results were found and what do they mean?
  • Conclusion : Were the results expected? Is this problem better understood now than before? If so, how?

How to write the introduction

The introduction is another summary, of sorts, so it could be easy to confuse the introduction with the abstract. While the abstract tends to be around 200 words summarizing the entire study, the introduction can be longer if necessary, covering background information on the study, what you aim to accomplish, and your hypothesis. Unlike the abstract (or the conclusion), the introduction does not need to state the results of the experiment.

Here is a possible order with which you can organize your lab report introduction:

  • Intro of the intro : Plainly state what your study is doing.
  • Background : Provide a brief overview of the topic being studied. This could include key terms and definitions. This should not be an extensive literature review, but rather, a window into the most relevant topics a reader would need to understand in order to understand your research.
  • Importance : Now, what are the gaps in existing research? Given the background you just provided, what questions do you still have that led you to conduct this experiment? Are you clarifying conflicting results? Are you undertaking a new area of research altogether?
  • Prediction: The plants placed by the window will grow faster than plants placed in the dark corner.
  • Hypothesis: Basil plants placed in direct sunlight for 2 hours per day grow at a higher rate than basil plants placed in direct sunlight for 30 minutes per day.
  • How you test your hypothesis : This is an opportunity to briefly state how you go about your experiment, but this is not the time to get into specific details about your methods (save this for your results section). Keep this part down to one sentence, and voila! You have your introduction.

How to write a discussion section

Here, we’re skipping ahead to the next writing-heavy section, which will directly follow the numeric data of your experiment. The discussion includes any calculations and interpretations based on this data. In other words, it says, “Now that we have the data, why should we care?”  This section asks, how does this data sit in relation to the hypothesis? Does it prove your hypothesis or disprove it? The discussion is also a good place to mention any mistakes that were made during the experiment, and ways you would improve the experiment if you were to repeat it. Like the other written sections, it should be as concise as possible.

Here is a list of points to cover in your lab report discussion:

  • Weaker statement: These findings prove that basil plants grow more quickly in the sunlight.
  • Stronger statement: These findings support the hypothesis that basil plants placed in direct sunlight grow at a higher rate than basil plants given less direct sunlight.
  • Factors influencing results : This is also an opportunity to mention any anomalies, errors, or inconsistencies in your data. Perhaps when you tested the first round of basil plants, the days were sunnier than the others. Perhaps one of the basil pots broke mid-experiment so it needed to be replanted, which affected your results. If you were to repeat the study, how would you change it so that the results were more consistent?
  • Implications : How do your results contribute to existing research? Here, refer back to the gaps in research that you mentioned in your introduction. Do these results fill these gaps as you hoped?
  • Questions for future research : Based on this, how might your results contribute to future research? What are the next steps, or the next experiments on this topic? Make sure this does not become too broad—keep it to the scope of this project.

How to write a lab report conclusion

This is your opportunity to briefly remind the reader of your findings and finish strong. Your conclusion should be especially concise (avoid going into detail on findings or introducing new information).

Here are elements to include as you write your conclusion, in about 1-2 sentences each:

  • Restate your goals : What was the main question of your experiment? Refer back to your introduction—similar language is okay.
  • Restate your methods : In a sentence or so, how did you go about your experiment?
  • Key findings : Briefly summarize your main results, but avoid going into detail.
  • Limitations : What about your experiment was less-than-ideal, and how could you improve upon the experiment in future studies?
  • Significance and future research : Why is your research important? What are the logical next-steps for studying this topic?

Template for beginning your lab report

Here is a compiled outline from the bullet points in these sections above, with some examples based on the (overly-simplistic) basil growth experiment. Hopefully this will be useful as you begin your lab report.

1) Title (ex: Effects of Sunlight on Basil Plant Growth )

2) Abstract (approx. 200 words)

  • Background ( This experiment looks at… )
  • Objectives ( It aims to contribute to research on…)
  • Methods ( It does so through a process of…. )
  • Results (Findings supported the hypothesis that… )
  • Conclusion (These results contribute to a wider understanding about…)

3) Introduction (approx. 1-2 paragraphs)

  • Intro ( This experiment looks at… )
  • Background ( Past studies on basil plant growth and sunlight have found…)
  • Importance ( This experiment will contribute to these past studies by…)
  • Hypothesis ( Basil plants placed in direct sunlight for 2 hours per day grow at a higher rate than basil plants placed in direct sunlight for 30 minutes per day.)
  • How you will test your hypothesis ( This hypothesis will be tested by a process of…)

4) Materials (list form) (ex: pots, soil, seeds, tables/stands, water, light source )

5) Methods (approx. 1-2 paragraphs) (ex: 10 basil plants were measured throughout a span of…)

6) Data (brief description and figures) (ex: These charts demonstrate a pattern that the basil plants placed in direct sunlight…)

7) Discussion (approx. 2-3 paragraphs)

  • Support or reject hypothesis ( These findings support the hypothesis that basil plants placed in direct sunlight grow at a higher rate than basil plants given less direct sunlight.)
  • Factors that influenced your results ( Outside factors that could have altered the results include…)
  • Implications ( These results contribute to current research on basil plant growth and sunlight because…)
  • Questions for further research ( Next steps for this research could include…)
  • Restate your goals ( In summary, the goal of this experiment was to measure…)
  • Restate your methods ( This hypothesis was tested by…)
  • Key findings ( The findings supported the hypothesis because…)
  • Limitations ( Although, certain elements were overlooked, including…)
  • Significance and future research ( This experiment presents possibilities of future research contributions, such as…)
  • Sources (approx. 1 page, usually in APA style)

Final thoughts – Lab Report Example

Hopefully, these descriptions have helped as you write your next lab report. Remember that different instructors may have different preferences for structure and format, so make sure to double-check when you receive your assignment. All in all, make sure to keep your scientific lab report concise, focused, honest, and organized. Good luck!

For more reading on coursework success, check out the following articles:

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With a BA from Wesleyan University and an MFA from the University of Illinois at Urbana-Champaign, Sarah is a writer, educator, and artist. She served as a graduate instructor at the University of Illinois, a tutor at St Peter’s School in Philadelphia, and an academic writing tutor and thesis mentor at Wesleyan’s Writing Workshop.

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How To Write A Lab Report | Step-by-Step Guide & Examples

Published on May 20, 2021 by Pritha Bhandari . Revised on July 23, 2023.

A lab report conveys the aim, methods, results, and conclusions of a scientific experiment. The main purpose of a lab report is to demonstrate your understanding of the scientific method by performing and evaluating a hands-on lab experiment. This type of assignment is usually shorter than a research paper .

Lab reports are commonly used in science, technology, engineering, and mathematics (STEM) fields. This article focuses on how to structure and write a lab report.

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Table of contents

Structuring a lab report, introduction, other interesting articles, frequently asked questions about lab reports.

The sections of a lab report can vary between scientific fields and course requirements, but they usually contain the purpose, methods, and findings of a lab experiment .

Each section of a lab report has its own purpose.

  • Title: expresses the topic of your study
  • Abstract : summarizes your research aims, methods, results, and conclusions
  • Introduction: establishes the context needed to understand the topic
  • Method: describes the materials and procedures used in the experiment
  • Results: reports all descriptive and inferential statistical analyses
  • Discussion: interprets and evaluates results and identifies limitations
  • Conclusion: sums up the main findings of your experiment
  • References: list of all sources cited using a specific style (e.g. APA )
  • Appendices : contains lengthy materials, procedures, tables or figures

Although most lab reports contain these sections, some sections can be omitted or combined with others. For example, some lab reports contain a brief section on research aims instead of an introduction, and a separate conclusion is not always required.

If you’re not sure, it’s best to check your lab report requirements with your instructor.

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Your title provides the first impression of your lab report – effective titles communicate the topic and/or the findings of your study in specific terms.

Create a title that directly conveys the main focus or purpose of your study. It doesn’t need to be creative or thought-provoking, but it should be informative.

  • The effects of varying nitrogen levels on tomato plant height.
  • Testing the universality of the McGurk effect.
  • Comparing the viscosity of common liquids found in kitchens.

An abstract condenses a lab report into a brief overview of about 150–300 words. It should provide readers with a compact version of the research aims, the methods and materials used, the main results, and the final conclusion.

Think of it as a way of giving readers a preview of your full lab report. Write the abstract last, in the past tense, after you’ve drafted all the other sections of your report, so you’ll be able to succinctly summarize each section.

To write a lab report abstract, use these guiding questions:

  • What is the wider context of your study?
  • What research question were you trying to answer?
  • How did you perform the experiment?
  • What did your results show?
  • How did you interpret your results?
  • What is the importance of your findings?

Nitrogen is a necessary nutrient for high quality plants. Tomatoes, one of the most consumed fruits worldwide, rely on nitrogen for healthy leaves and stems to grow fruit. This experiment tested whether nitrogen levels affected tomato plant height in a controlled setting. It was expected that higher levels of nitrogen fertilizer would yield taller tomato plants.

Levels of nitrogen fertilizer were varied between three groups of tomato plants. The control group did not receive any nitrogen fertilizer, while one experimental group received low levels of nitrogen fertilizer, and a second experimental group received high levels of nitrogen fertilizer. All plants were grown from seeds, and heights were measured 50 days into the experiment.

The effects of nitrogen levels on plant height were tested between groups using an ANOVA. The plants with the highest level of nitrogen fertilizer were the tallest, while the plants with low levels of nitrogen exceeded the control group plants in height. In line with expectations and previous findings, the effects of nitrogen levels on plant height were statistically significant. This study strengthens the importance of nitrogen for tomato plants.

Your lab report introduction should set the scene for your experiment. One way to write your introduction is with a funnel (an inverted triangle) structure:

  • Start with the broad, general research topic
  • Narrow your topic down your specific study focus
  • End with a clear research question

Begin by providing background information on your research topic and explaining why it’s important in a broad real-world or theoretical context. Describe relevant previous research on your topic and note how your study may confirm it or expand it, or fill a gap in the research field.

This lab experiment builds on previous research from Haque, Paul, and Sarker (2011), who demonstrated that tomato plant yield increased at higher levels of nitrogen. However, the present research focuses on plant height as a growth indicator and uses a lab-controlled setting instead.

Next, go into detail on the theoretical basis for your study and describe any directly relevant laws or equations that you’ll be using. State your main research aims and expectations by outlining your hypotheses .

Based on the importance of nitrogen for tomato plants, the primary hypothesis was that the plants with the high levels of nitrogen would grow the tallest. The secondary hypothesis was that plants with low levels of nitrogen would grow taller than plants with no nitrogen.

Your introduction doesn’t need to be long, but you may need to organize it into a few paragraphs or with subheadings such as “Research Context” or “Research Aims.”

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example of a hypothesis in a lab report

A lab report Method section details the steps you took to gather and analyze data. Give enough detail so that others can follow or evaluate your procedures. Write this section in the past tense. If you need to include any long lists of procedural steps or materials, place them in the Appendices section but refer to them in the text here.

You should describe your experimental design, your subjects, materials, and specific procedures used for data collection and analysis.

Experimental design

Briefly note whether your experiment is a within-subjects  or between-subjects design, and describe how your sample units were assigned to conditions if relevant.

A between-subjects design with three groups of tomato plants was used. The control group did not receive any nitrogen fertilizer. The first experimental group received a low level of nitrogen fertilizer, while the second experimental group received a high level of nitrogen fertilizer.

Describe human subjects in terms of demographic characteristics, and animal or plant subjects in terms of genetic background. Note the total number of subjects as well as the number of subjects per condition or per group. You should also state how you recruited subjects for your study.

List the equipment or materials you used to gather data and state the model names for any specialized equipment.

List of materials

35 Tomato seeds

15 plant pots (15 cm tall)

Light lamps (50,000 lux)

Nitrogen fertilizer

Measuring tape

Describe your experimental settings and conditions in detail. You can provide labelled diagrams or images of the exact set-up necessary for experimental equipment. State how extraneous variables were controlled through restriction or by fixing them at a certain level (e.g., keeping the lab at room temperature).

Light levels were fixed throughout the experiment, and the plants were exposed to 12 hours of light a day. Temperature was restricted to between 23 and 25℃. The pH and carbon levels of the soil were also held constant throughout the experiment as these variables could influence plant height. The plants were grown in rooms free of insects or other pests, and they were spaced out adequately.

Your experimental procedure should describe the exact steps you took to gather data in chronological order. You’ll need to provide enough information so that someone else can replicate your procedure, but you should also be concise. Place detailed information in the appendices where appropriate.

In a lab experiment, you’ll often closely follow a lab manual to gather data. Some instructors will allow you to simply reference the manual and state whether you changed any steps based on practical considerations. Other instructors may want you to rewrite the lab manual procedures as complete sentences in coherent paragraphs, while noting any changes to the steps that you applied in practice.

If you’re performing extensive data analysis, be sure to state your planned analysis methods as well. This includes the types of tests you’ll perform and any programs or software you’ll use for calculations (if relevant).

First, tomato seeds were sown in wooden flats containing soil about 2 cm below the surface. Each seed was kept 3-5 cm apart. The flats were covered to keep the soil moist until germination. The seedlings were removed and transplanted to pots 8 days later, with a maximum of 2 plants to a pot. Each pot was watered once a day to keep the soil moist.

The nitrogen fertilizer treatment was applied to the plant pots 12 days after transplantation. The control group received no treatment, while the first experimental group received a low concentration, and the second experimental group received a high concentration. There were 5 pots in each group, and each plant pot was labelled to indicate the group the plants belonged to.

50 days after the start of the experiment, plant height was measured for all plants. A measuring tape was used to record the length of the plant from ground level to the top of the tallest leaf.

In your results section, you should report the results of any statistical analysis procedures that you undertook. You should clearly state how the results of statistical tests support or refute your initial hypotheses.

The main results to report include:

  • any descriptive statistics
  • statistical test results
  • the significance of the test results
  • estimates of standard error or confidence intervals

The mean heights of the plants in the control group, low nitrogen group, and high nitrogen groups were 20.3, 25.1, and 29.6 cm respectively. A one-way ANOVA was applied to calculate the effect of nitrogen fertilizer level on plant height. The results demonstrated statistically significant ( p = .03) height differences between groups.

Next, post-hoc tests were performed to assess the primary and secondary hypotheses. In support of the primary hypothesis, the high nitrogen group plants were significantly taller than the low nitrogen group and the control group plants. Similarly, the results supported the secondary hypothesis: the low nitrogen plants were taller than the control group plants.

These results can be reported in the text or in tables and figures. Use text for highlighting a few key results, but present large sets of numbers in tables, or show relationships between variables with graphs.

You should also include sample calculations in the Results section for complex experiments. For each sample calculation, provide a brief description of what it does and use clear symbols. Present your raw data in the Appendices section and refer to it to highlight any outliers or trends.

The Discussion section will help demonstrate your understanding of the experimental process and your critical thinking skills.

In this section, you can:

  • Interpret your results
  • Compare your findings with your expectations
  • Identify any sources of experimental error
  • Explain any unexpected results
  • Suggest possible improvements for further studies

Interpreting your results involves clarifying how your results help you answer your main research question. Report whether your results support your hypotheses.

  • Did you measure what you sought out to measure?
  • Were your analysis procedures appropriate for this type of data?

Compare your findings with other research and explain any key differences in findings.

  • Are your results in line with those from previous studies or your classmates’ results? Why or why not?

An effective Discussion section will also highlight the strengths and limitations of a study.

  • Did you have high internal validity or reliability?
  • How did you establish these aspects of your study?

When describing limitations, use specific examples. For example, if random error contributed substantially to the measurements in your study, state the particular sources of error (e.g., imprecise apparatus) and explain ways to improve them.

The results support the hypothesis that nitrogen levels affect plant height, with increasing levels producing taller plants. These statistically significant results are taken together with previous research to support the importance of nitrogen as a nutrient for tomato plant growth.

However, unlike previous studies, this study focused on plant height as an indicator of plant growth in the present experiment. Importantly, plant height may not always reflect plant health or fruit yield, so measuring other indicators would have strengthened the study findings.

Another limitation of the study is the plant height measurement technique, as the measuring tape was not suitable for plants with extreme curvature. Future studies may focus on measuring plant height in different ways.

The main strengths of this study were the controls for extraneous variables, such as pH and carbon levels of the soil. All other factors that could affect plant height were tightly controlled to isolate the effects of nitrogen levels, resulting in high internal validity for this study.

Your conclusion should be the final section of your lab report. Here, you’ll summarize the findings of your experiment, with a brief overview of the strengths and limitations, and implications of your study for further research.

Some lab reports may omit a Conclusion section because it overlaps with the Discussion section, but you should check with your instructor before doing so.

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A lab report conveys the aim, methods, results, and conclusions of a scientific experiment . Lab reports are commonly assigned in science, technology, engineering, and mathematics (STEM) fields.

The purpose of a lab report is to demonstrate your understanding of the scientific method with a hands-on lab experiment. Course instructors will often provide you with an experimental design and procedure. Your task is to write up how you actually performed the experiment and evaluate the outcome.

In contrast, a research paper requires you to independently develop an original argument. It involves more in-depth research and interpretation of sources and data.

A lab report is usually shorter than a research paper.

The sections of a lab report can vary between scientific fields and course requirements, but it usually contains the following:

  • Abstract: summarizes your research aims, methods, results, and conclusions
  • References: list of all sources cited using a specific style (e.g. APA)
  • Appendices: contains lengthy materials, procedures, tables or figures

The results chapter or section simply and objectively reports what you found, without speculating on why you found these results. The discussion interprets the meaning of the results, puts them in context, and explains why they matter.

In qualitative research , results and discussion are sometimes combined. But in quantitative research , it’s considered important to separate the objective results from your interpretation of them.

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How to Write Hypothesis for Lab Report

  • How to Write Hypothesis for…

What Is a Real Hypothesis?

A hypothesis is a tentative statement that proposes a possible explanation for some phenomenon or event. A useful hypothesis is a testable statement that may include a prediction.

When Are Hypotheses Used?

The keyword is testable. That is, you will perform a test of how two variables might be related. This is when you are doing a real experiment. You are testing variables. Usually, a hypothesis is based on some previous observations such as noticing that in November many trees undergo color changes in their leaves and the average daily temperatures are dropping. Are these two events connected? How?

Any laboratory procedure you follow without a hypothesis is really not an experiment. It is just an exercise or demonstration of what is already known.

How Are Hypotheses Written?

  • Chocolate may cause pimples.
  • Salt in soil may affect plant growth.
  • Plant growth may be affected by the color of the light.
  • Bacterial growth may be affected by temperature.
  • Ultraviolet light may cause skin cancer.
  • The temperature may cause leaves to change color.

All of these are examples of hypotheses because they use the tentative word “may.”. However, their form is not particularly useful. Using the word may do not suggest how you would go about proving it. If these statements had not been written carefully, they may not have even been hypotheses at all. For example, if we say “Trees will change color when it gets cold.” we are making a prediction. Or if we write, “Ultraviolet light causes skin cancer.” could be a conclusion. One way to prevent making such easy mistakes is to formalize the form of the hypothesis.

Formalized Hypotheses example: If the incidence of skin cancer is related to exposure levels of ultraviolet light , then people with a high exposure to uv light will have a higher frequency of skin cancer.

If leaf color change is related to temperature , then exposing plants to low temperatures will result in changes in leaf color .

Notice that these statements contain the words, if and then. They are necessary for a formalized hypothesis. But not all if-then statements are hypotheses. For example, “If I play the lottery, then I will get rich.” This is a simple prediction. In a formalized hypothesis, a tentative relationship is stated. For example, if the frequency of winning is related to the frequency of buying lottery tickets . “Then” is followed by a prediction of what will happen if you increase or decrease the frequency of buying lottery tickets. If you always ask yourself that if one thing is related to another, then you should be able to test it.

Formalized hypotheses contain two variables. One is “independent” and the other is “dependent.” The independent variable is the one you, the “scientist” control, and the dependent variable is the one that you observe and/or measure the results. In the statements above the dependent variable is underlined and the independent variable is underlined and italicized .

The ultimate value of a formalized hypothesis is it forces us to think about what results we should look for in an experiment.

For the “ If, Then, Because ” hypothesis…you would use: “ IF pigs and humans share the same nutritional behaviors, THEN their internal organs should look relatively the same BECAUSE of similar function and composure.” That is an example. For the “If, Then, Because” you should follow this guideline:

IF X and Y both do or share this, THEN this should be found/confirmed, BECAUSE of this fact or logical assumption.

Example Question : How does the type of liquid (water, milk, or orange juice) given to a plant affect how tall the plant will grow? Hypothesis : If the plant is given water then the plant will grow the tallest because water helps the plant absorb the nutrients that the plant needs to survive.

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16 Comments

How would I write a hypothesis about a flying pig lab?

your lab hypothesis should have been written before the experiment. The purpose of the hypothesis was to create a testable statement in which your experimental data would either support or reject. Having a hypothesis based on a logical assumption (regardless of whether your data supports it) is still correct. If there is a disagreement between your hypothesis and experimental data it should be addressed in the discussion.

So you can go ahead an choose a hypothesis for either increase or decrease of adipogenesis after the inducement of insulin and not be wrong….as long as it is correctly formatted (see examples above).

Hey, I am having trouble writing my hypothesis.. I am supposed to write a hypothesis about how much adipogenesis was produced after the inducement of insulin. However, after proceeding with the experiments the results were On/Off .. meaning it will increase, decrease, increase, etc.. so it wasnt a constant result. It was supposed to be increasing.

please help!!!

this is very helpful but i don’t know how i would structure my hypothesis. i’m supposed to come up with a hypothesis related to the topic ‘how does mass effect the stopping distance of a cart?’. Could you help?

Thank you so much, it really help alot.:)

This is a rather difficult usage of this construct. It would most likely follow

“If the empirical formula of (enter compound’s name) is (enter compound’s formula) then it would be expected that combustion of _________ would yield _________, because (enter your rationale)

Need more background info.

For the “If, then, because” hypothesis I am doing an experiment to determine the empirical formula by using combustion but I am unsure on how to formulate the hypothesis using this structure.

For the “If, Then, Because” hypothesis…you would use: “IF pigs and humans share the same nutritional behaviors, THEN their internal organs should look relatively the same BECAUSE of similar function and composure.” That is an example. For the “If, Then, Because” you should follow this guideline:

Thanks, really helpful. Just one question, what about the ‘because’ part? right after the ‘if’ and ‘then’ parts?

I really need help for onion skin lab hypothesis for class

@Lauren An if/and statement is not usually apart of the convention. What exactly do you need help with?

Is there such thing as a if/and statement? I am in 8th grade science an I need to know for my lab report due tomorrow.HELP!!!!

Would have been better if more examples were given

If the purpose of your lab is “To obtain dissecting skills in an observational lab,” you can’t really formulate a testable hypothesis for that. I’ll assume you are doing some kind of pig or frog dissection. Often teachers give general outlines of skills that students are meant to ascertain from an experiment which aren’t necessarily what the actual experiment is directly testing. Obviously to do the dissection lab you need to obtain dissection skills but testing that would be rather subjective unless the teacher provided you with standards or operationally defined “dissecting skills”. If I were you, I would obviously mention it in the introduction of your lab but I am not sure if your teacher wants you to actually format it as a hypothesis; you can ask your teacher for clarification. If making a hypothesis from each purpose was some arbitrary exercise assigned to you then, it could look like this:

“If a student has successful acquired dissection skills, then they will be able to complete this observational lab with satisfactory competence because they utilized these newly acquired skills.”

For the “If, Then, Because” hypothesis…you pretty much have it. You would modify what you posted: “IF pigs and humans share the same nutritional behaviors, THEN their internal organs should look relatively the same BECAUSE of similar function and composure.” That is an example. For the “If, Then, Because” you should follow this guideline:

Thanks for this, it proved to be helpful. However, I do have a few questions. Obviously different teachers or instructors have their own requirements for their classes. How would you write an appropriate Question to follow each purpose in your lab report? For example: If the purpose was, “To obtain dissecting skills in an observational lab,” what question could you formulate with the purpose? (which is answered in the hypothesis)

And if a teacher requires the hypothesis to be in the format “If, Then, Because” how should this be written? I can actively complete the if and then, but I’m unsure how to incorporate the “because’ statement. For example, “If pigs and humans share the same nutritional behaviors, then their internal organs should function comparably and look relatively the same.” (how do i incorporate because?)

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Lab Report Format: Step-by-Step Guide & Examples

Saul Mcleod, PhD

Editor-in-Chief for Simply Psychology

BSc (Hons) Psychology, MRes, PhD, University of Manchester

Saul Mcleod, PhD., is a qualified psychology teacher with over 18 years of experience in further and higher education. He has been published in peer-reviewed journals, including the Journal of Clinical Psychology.

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Olivia Guy-Evans, MSc

Associate Editor for Simply Psychology

BSc (Hons) Psychology, MSc Psychology of Education

Olivia Guy-Evans is a writer and associate editor for Simply Psychology. She has previously worked in healthcare and educational sectors.

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In psychology, a lab report outlines a study’s objectives, methods, results, discussion, and conclusions, ensuring clarity and adherence to APA (or relevant) formatting guidelines.

A typical lab report would include the following sections: title, abstract, introduction, method, results, and discussion.

The title page, abstract, references, and appendices are started on separate pages (subsections from the main body of the report are not). Use double-line spacing of text, font size 12, and include page numbers.

The report should have a thread of arguments linking the prediction in the introduction to the content of the discussion.

This must indicate what the study is about. It must include the variables under investigation. It should not be written as a question.

Title pages should be formatted in APA style .

The abstract provides a concise and comprehensive summary of a research report. Your style should be brief but not use note form. Look at examples in journal articles . It should aim to explain very briefly (about 150 words) the following:

  • Start with a one/two sentence summary, providing the aim and rationale for the study.
  • Describe participants and setting: who, when, where, how many, and what groups?
  • Describe the method: what design, what experimental treatment, what questionnaires, surveys, or tests were used.
  • Describe the major findings, including a mention of the statistics used and the significance levels, or simply one sentence summing up the outcome.
  • The final sentence(s) outline the study’s “contribution to knowledge” within the literature. What does it all mean? Mention the implications of your findings if appropriate.

The abstract comes at the beginning of your report but is written at the end (as it summarises information from all the other sections of the report).

Introduction

The purpose of the introduction is to explain where your hypothesis comes from (i.e., it should provide a rationale for your research study).

Ideally, the introduction should have a funnel structure: Start broad and then become more specific. The aims should not appear out of thin air; the preceding review of psychological literature should lead logically into the aims and hypotheses.

The funnel structure of the introducion to a lab report

  • Start with general theory, briefly introducing the topic. Define the important key terms.
  • Explain the theoretical framework.
  • Summarise and synthesize previous studies – What was the purpose? Who were the participants? What did they do? What did they find? What do these results mean? How do the results relate to the theoretical framework?
  • Rationale: How does the current study address a gap in the literature? Perhaps it overcomes a limitation of previous research.
  • Aims and hypothesis. Write a paragraph explaining what you plan to investigate and make a clear and concise prediction regarding the results you expect to find.

There should be a logical progression of ideas that aids the flow of the report. This means the studies outlined should lead logically to your aims and hypotheses.

Do be concise and selective, and avoid the temptation to include anything in case it is relevant (i.e., don’t write a shopping list of studies).

USE THE FOLLOWING SUBHEADINGS:

Participants

  • How many participants were recruited?
  • Say how you obtained your sample (e.g., opportunity sample).
  • Give relevant demographic details (e.g., gender, ethnicity, age range, mean age, and standard deviation).
  • State the experimental design .
  • What were the independent and dependent variables ? Make sure the independent variable is labeled and name the different conditions/levels.
  • For example, if gender is the independent variable label, then male and female are the levels/conditions/groups.
  • How were the IV and DV operationalized?
  • Identify any controls used, e.g., counterbalancing and control of extraneous variables.
  • List all the materials and measures (e.g., what was the title of the questionnaire? Was it adapted from a study?).
  • You do not need to include wholesale replication of materials – instead, include a ‘sensible’ (illustrate) level of detail. For example, give examples of questionnaire items.
  • Include the reliability (e.g., alpha values) for the measure(s).
  • Describe the precise procedure you followed when conducting your research, i.e., exactly what you did.
  • Describe in sufficient detail to allow for replication of findings.
  • Be concise in your description and omit extraneous/trivial details, e.g., you don’t need to include details regarding instructions, debrief, record sheets, etc.
  • Assume the reader has no knowledge of what you did and ensure that he/she can replicate (i.e., copy) your study exactly by what you write in this section.
  • Write in the past tense.
  • Don’t justify or explain in the Method (e.g., why you chose a particular sampling method); just report what you did.
  • Only give enough detail for someone to replicate the experiment – be concise in your writing.
  • The results section of a paper usually presents descriptive statistics followed by inferential statistics.
  • Report the means, standard deviations, and 95% confidence intervals (CIs) for each IV level. If you have four to 20 numbers to present, a well-presented table is best, APA style.
  • Name the statistical test being used.
  • Report appropriate statistics (e.g., t-scores, p values ).
  • Report the magnitude (e.g., are the results significant or not?) as well as the direction of the results (e.g., which group performed better?).
  • It is optional to report the effect size (this does not appear on the SPSS output).
  • Avoid interpreting the results (save this for the discussion).
  • Make sure the results are presented clearly and concisely. A table can be used to display descriptive statistics if this makes the data easier to understand.
  • DO NOT include any raw data.
  • Follow APA style.

Use APA Style

  • Numbers reported to 2 d.p. (incl. 0 before the decimal if 1.00, e.g., “0.51”). The exceptions to this rule: Numbers which can never exceed 1.0 (e.g., p -values, r-values): report to 3 d.p. and do not include 0 before the decimal place, e.g., “.001”.
  • Percentages and degrees of freedom: report as whole numbers.
  • Statistical symbols that are not Greek letters should be italicized (e.g., M , SD , t , X 2 , F , p , d ).
  • Include spaces on either side of the equals sign.
  • When reporting 95%, CIs (confidence intervals), upper and lower limits are given inside square brackets, e.g., “95% CI [73.37, 102.23]”
  • Outline your findings in plain English (avoid statistical jargon) and relate your results to your hypothesis, e.g., is it supported or rejected?
  • Compare your results to background materials from the introduction section. Are your results similar or different? Discuss why/why not.
  • How confident can we be in the results? Acknowledge limitations, but only if they can explain the result obtained. If the study has found a reliable effect, be very careful suggesting limitations as you are doubting your results. Unless you can think of any c onfounding variable that can explain the results instead of the IV, it would be advisable to leave the section out.
  • Suggest constructive ways to improve your study if appropriate.
  • What are the implications of your findings? Say what your findings mean for how people behave in the real world.
  • Suggest an idea for further research triggered by your study, something in the same area but not simply an improved version of yours. Perhaps you could base this on a limitation of your study.
  • Concluding paragraph – Finish with a statement of your findings and the key points of the discussion (e.g., interpretation and implications) in no more than 3 or 4 sentences.

Reference Page

The reference section lists all the sources cited in the essay (alphabetically). It is not a bibliography (a list of the books you used).

In simple terms, every time you refer to a psychologist’s name (and date), you need to reference the original source of information.

If you have been using textbooks this is easy as the references are usually at the back of the book and you can just copy them down. If you have been using websites then you may have a problem as they might not provide a reference section for you to copy.

References need to be set out APA style :

Author, A. A. (year). Title of work . Location: Publisher.

Journal Articles

Author, A. A., Author, B. B., & Author, C. C. (year). Article title. Journal Title, volume number (issue number), page numbers

A simple way to write your reference section is to use Google scholar . Just type the name and date of the psychologist in the search box and click on the “cite” link.

google scholar search results

Next, copy and paste the APA reference into the reference section of your essay.

apa reference

Once again, remember that references need to be in alphabetical order according to surname.

Psychology Lab Report Example

Quantitative paper template.

Quantitative professional paper template: Adapted from “Fake News, Fast and Slow: Deliberation Reduces Belief in False (but Not True) News Headlines,” by B. Bago, D. G. Rand, and G. Pennycook, 2020,  Journal of Experimental Psychology: General ,  149 (8), pp. 1608–1613 ( https://doi.org/10.1037/xge0000729 ). Copyright 2020 by the American Psychological Association.

Qualitative paper template

Qualitative professional paper template: Adapted from “‘My Smartphone Is an Extension of Myself’: A Holistic Qualitative Exploration of the Impact of Using a Smartphone,” by L. J. Harkin and D. Kuss, 2020,  Psychology of Popular Media ,  10 (1), pp. 28–38 ( https://doi.org/10.1037/ppm0000278 ). Copyright 2020 by the American Psychological Association.

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  • How to Write a Strong Hypothesis | Guide & Examples

How to Write a Strong Hypothesis | Guide & Examples

Published on 6 May 2022 by Shona McCombes .

A hypothesis is a statement that can be tested by scientific research. If you want to test a relationship between two or more variables, you need to write hypotheses before you start your experiment or data collection.

Table of contents

What is a hypothesis, developing a hypothesis (with example), hypothesis examples, frequently asked questions about writing hypotheses.

A hypothesis states your predictions about what your research will find. It is a tentative answer to your research question that has not yet been tested. For some research projects, you might have to write several hypotheses that address different aspects of your research question.

A hypothesis is not just a guess – it should be based on existing theories and knowledge. It also has to be testable, which means you can support or refute it through scientific research methods (such as experiments, observations, and statistical analysis of data).

Variables in hypotheses

Hypotheses propose a relationship between two or more variables . An independent variable is something the researcher changes or controls. A dependent variable is something the researcher observes and measures.

In this example, the independent variable is exposure to the sun – the assumed cause . The dependent variable is the level of happiness – the assumed effect .

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Step 1: ask a question.

Writing a hypothesis begins with a research question that you want to answer. The question should be focused, specific, and researchable within the constraints of your project.

Step 2: Do some preliminary research

Your initial answer to the question should be based on what is already known about the topic. Look for theories and previous studies to help you form educated assumptions about what your research will find.

At this stage, you might construct a conceptual framework to identify which variables you will study and what you think the relationships are between them. Sometimes, you’ll have to operationalise more complex constructs.

Step 3: Formulate your hypothesis

Now you should have some idea of what you expect to find. Write your initial answer to the question in a clear, concise sentence.

Step 4: Refine your hypothesis

You need to make sure your hypothesis is specific and testable. There are various ways of phrasing a hypothesis, but all the terms you use should have clear definitions, and the hypothesis should contain:

  • The relevant variables
  • The specific group being studied
  • The predicted outcome of the experiment or analysis

Step 5: Phrase your hypothesis in three ways

To identify the variables, you can write a simple prediction in if … then form. The first part of the sentence states the independent variable and the second part states the dependent variable.

In academic research, hypotheses are more commonly phrased in terms of correlations or effects, where you directly state the predicted relationship between variables.

If you are comparing two groups, the hypothesis can state what difference you expect to find between them.

Step 6. Write a null hypothesis

If your research involves statistical hypothesis testing , you will also have to write a null hypothesis. The null hypothesis is the default position that there is no association between the variables. The null hypothesis is written as H 0 , while the alternative hypothesis is H 1 or H a .

Research question Hypothesis Null hypothesis
What are the health benefits of eating an apple a day? Increasing apple consumption in over-60s will result in decreasing frequency of doctor’s visits. Increasing apple consumption in over-60s will have no effect on frequency of doctor’s visits.
Which airlines have the most delays? Low-cost airlines are more likely to have delays than premium airlines. Low-cost and premium airlines are equally likely to have delays.
Can flexible work arrangements improve job satisfaction? Employees who have flexible working hours will report greater job satisfaction than employees who work fixed hours. There is no relationship between working hour flexibility and job satisfaction.
How effective is secondary school sex education at reducing teen pregnancies? Teenagers who received sex education lessons throughout secondary school will have lower rates of unplanned pregnancy than teenagers who did not receive any sex education. Secondary school sex education has no effect on teen pregnancy rates.
What effect does daily use of social media have on the attention span of under-16s? There is a negative correlation between time spent on social media and attention span in under-16s. There is no relationship between social media use and attention span in under-16s.

Hypothesis testing is a formal procedure for investigating our ideas about the world using statistics. It is used by scientists to test specific predictions, called hypotheses , by calculating how likely it is that a pattern or relationship between variables could have arisen by chance.

A hypothesis is not just a guess. It should be based on existing theories and knowledge. It also has to be testable, which means you can support or refute it through scientific research methods (such as experiments, observations, and statistical analysis of data).

A research hypothesis is your proposed answer to your research question. The research hypothesis usually includes an explanation (‘ x affects y because …’).

A statistical hypothesis, on the other hand, is a mathematical statement about a population parameter. Statistical hypotheses always come in pairs: the null and alternative hypotheses. In a well-designed study , the statistical hypotheses correspond logically to the research hypothesis.

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Shona McCombes

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Other students also liked, operationalisation | a guide with examples, pros & cons, what is a conceptual framework | tips & examples, a quick guide to experimental design | 5 steps & examples.

How to Write a Lab Report

Lab Reports Describe Your Experiment

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Lab reports are an essential part of all laboratory courses and usually a significant part of your grade. If your instructor gives you an outline for how to write a lab report, use that. Some instructors require a lab report to be included in a lab notebook , while others will request a separate report. Here's how to write a lab report you can use if you aren't sure what to write or need an explanation of what to include in the different parts of the report.

A lab report is how you explain what you did in ​your experiment, what you learned, and what the results meant.

Lab Report Essentials

Not all lab reports have title pages, but if your instructor wants one, it would be a single page that states:​

  • The title of the experiment.
  • Your name and the names of any lab partners.
  • Your instructor's name.
  • The date the experiment was performed or the date the report was submitted.

The title says what you did. It should be brief (aim for ten words or less) and describe the main point of the experiment or investigation. An example of a title would be: "Effects of Ultraviolet Light on Borax Crystal Growth Rate". If you can, begin your title using a keyword rather than an article like "The" or "A".

Introduction or Purpose

Usually, the introduction is one paragraph that explains the objectives or purpose of the lab. In one sentence, state the hypothesis. Sometimes an introduction may contain background information, briefly summarize how the experiment was performed, state the findings of the experiment, and list the conclusions of the investigation. Even if you don't write a whole introduction, you need to state the purpose of the experiment, or why you did it. This would be where you state your hypothesis .

List everything needed to complete your experiment.

Describe the steps you completed during your investigation. This is your procedure. Be sufficiently detailed so that anyone can read this section and duplicate your experiment. Write it as if you were giving directions for someone else to do the lab. It may be helpful to provide a figure to diagram your experimental setup.

Numerical data obtained from your procedure usually presented as a table. Data encompasses what you recorded when you conducted the experiment. It's just the facts, not any interpretation of what they mean.

Describe in words what the data means. Sometimes the Results section is combined with the Discussion.

Discussion or Analysis

The Data section contains numbers; the Analysis section contains any calculations you made based on those numbers. This is where you interpret the data and determine whether or not a hypothesis was accepted. This is also where you would discuss any mistakes you might have made while conducting the investigation. You may wish to describe ways the study might have been improved.

Conclusions

Most of the time the conclusion is a single paragraph that sums up what happened in the experiment, whether your hypothesis was accepted or rejected, and what this means.

Figures and Graphs

Graphs and figures must both be labeled with a descriptive title. Label the axes on a graph, being sure to include units of measurement. The independent variable is on the X-axis, and the dependent variable (the one you are measuring) is on the Y-axis. Be sure to refer to figures and graphs in the text of your report: the first figure is Figure 1, the second figure is Figure 2, etc.

If your research was based on someone else's work or if you cited facts that require documentation, then you should list these references.

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The Writing Center • University of North Carolina at Chapel Hill

Scientific Reports

What this handout is about.

This handout provides a general guide to writing reports about scientific research you’ve performed. In addition to describing the conventional rules about the format and content of a lab report, we’ll also attempt to convey why these rules exist, so you’ll get a clearer, more dependable idea of how to approach this writing situation. Readers of this handout may also find our handout on writing in the sciences useful.

Background and pre-writing

Why do we write research reports.

You did an experiment or study for your science class, and now you have to write it up for your teacher to review. You feel that you understood the background sufficiently, designed and completed the study effectively, obtained useful data, and can use those data to draw conclusions about a scientific process or principle. But how exactly do you write all that? What is your teacher expecting to see?

To take some of the guesswork out of answering these questions, try to think beyond the classroom setting. In fact, you and your teacher are both part of a scientific community, and the people who participate in this community tend to share the same values. As long as you understand and respect these values, your writing will likely meet the expectations of your audience—including your teacher.

So why are you writing this research report? The practical answer is “Because the teacher assigned it,” but that’s classroom thinking. Generally speaking, people investigating some scientific hypothesis have a responsibility to the rest of the scientific world to report their findings, particularly if these findings add to or contradict previous ideas. The people reading such reports have two primary goals:

  • They want to gather the information presented.
  • They want to know that the findings are legitimate.

Your job as a writer, then, is to fulfill these two goals.

How do I do that?

Good question. Here is the basic format scientists have designed for research reports:

  • Introduction

Methods and Materials

This format, sometimes called “IMRAD,” may take slightly different shapes depending on the discipline or audience; some ask you to include an abstract or separate section for the hypothesis, or call the Discussion section “Conclusions,” or change the order of the sections (some professional and academic journals require the Methods section to appear last). Overall, however, the IMRAD format was devised to represent a textual version of the scientific method.

The scientific method, you’ll probably recall, involves developing a hypothesis, testing it, and deciding whether your findings support the hypothesis. In essence, the format for a research report in the sciences mirrors the scientific method but fleshes out the process a little. Below, you’ll find a table that shows how each written section fits into the scientific method and what additional information it offers the reader.

states your hypothesis explains how you derived that hypothesis and how it connects to previous research; gives the purpose of the experiment/study
details how you tested your hypothesis clarifies why you performed your study in that particular way
provides raw (i.e., uninterpreted) data collected (perhaps) expresses the data in table form, as an easy-to-read figure, or as percentages/ratios
considers whether the data you obtained support the hypothesis explores the implications of your finding and judges the potential limitations of your experimental design

Thinking of your research report as based on the scientific method, but elaborated in the ways described above, may help you to meet your audience’s expectations successfully. We’re going to proceed by explicitly connecting each section of the lab report to the scientific method, then explaining why and how you need to elaborate that section.

Although this handout takes each section in the order in which it should be presented in the final report, you may for practical reasons decide to compose sections in another order. For example, many writers find that composing their Methods and Results before the other sections helps to clarify their idea of the experiment or study as a whole. You might consider using each assignment to practice different approaches to drafting the report, to find the order that works best for you.

What should I do before drafting the lab report?

The best way to prepare to write the lab report is to make sure that you fully understand everything you need to about the experiment. Obviously, if you don’t quite know what went on during the lab, you’re going to find it difficult to explain the lab satisfactorily to someone else. To make sure you know enough to write the report, complete the following steps:

  • What are we going to do in this lab? (That is, what’s the procedure?)
  • Why are we going to do it that way?
  • What are we hoping to learn from this experiment?
  • Why would we benefit from this knowledge?
  • Consult your lab supervisor as you perform the lab. If you don’t know how to answer one of the questions above, for example, your lab supervisor will probably be able to explain it to you (or, at least, help you figure it out).
  • Plan the steps of the experiment carefully with your lab partners. The less you rush, the more likely it is that you’ll perform the experiment correctly and record your findings accurately. Also, take some time to think about the best way to organize the data before you have to start putting numbers down. If you can design a table to account for the data, that will tend to work much better than jotting results down hurriedly on a scrap piece of paper.
  • Record the data carefully so you get them right. You won’t be able to trust your conclusions if you have the wrong data, and your readers will know you messed up if the other three people in your group have “97 degrees” and you have “87.”
  • Consult with your lab partners about everything you do. Lab groups often make one of two mistakes: two people do all the work while two have a nice chat, or everybody works together until the group finishes gathering the raw data, then scrams outta there. Collaborate with your partners, even when the experiment is “over.” What trends did you observe? Was the hypothesis supported? Did you all get the same results? What kind of figure should you use to represent your findings? The whole group can work together to answer these questions.
  • Consider your audience. You may believe that audience is a non-issue: it’s your lab TA, right? Well, yes—but again, think beyond the classroom. If you write with only your lab instructor in mind, you may omit material that is crucial to a complete understanding of your experiment, because you assume the instructor knows all that stuff already. As a result, you may receive a lower grade, since your TA won’t be sure that you understand all the principles at work. Try to write towards a student in the same course but a different lab section. That student will have a fair degree of scientific expertise but won’t know much about your experiment particularly. Alternatively, you could envision yourself five years from now, after the reading and lectures for this course have faded a bit. What would you remember, and what would you need explained more clearly (as a refresher)?

Once you’ve completed these steps as you perform the experiment, you’ll be in a good position to draft an effective lab report.

Introductions

How do i write a strong introduction.

For the purposes of this handout, we’ll consider the Introduction to contain four basic elements: the purpose, the scientific literature relevant to the subject, the hypothesis, and the reasons you believed your hypothesis viable. Let’s start by going through each element of the Introduction to clarify what it covers and why it’s important. Then we can formulate a logical organizational strategy for the section.

The inclusion of the purpose (sometimes called the objective) of the experiment often confuses writers. The biggest misconception is that the purpose is the same as the hypothesis. Not quite. We’ll get to hypotheses in a minute, but basically they provide some indication of what you expect the experiment to show. The purpose is broader, and deals more with what you expect to gain through the experiment. In a professional setting, the hypothesis might have something to do with how cells react to a certain kind of genetic manipulation, but the purpose of the experiment is to learn more about potential cancer treatments. Undergraduate reports don’t often have this wide-ranging a goal, but you should still try to maintain the distinction between your hypothesis and your purpose. In a solubility experiment, for example, your hypothesis might talk about the relationship between temperature and the rate of solubility, but the purpose is probably to learn more about some specific scientific principle underlying the process of solubility.

For starters, most people say that you should write out your working hypothesis before you perform the experiment or study. Many beginning science students neglect to do so and find themselves struggling to remember precisely which variables were involved in the process or in what way the researchers felt that they were related. Write your hypothesis down as you develop it—you’ll be glad you did.

As for the form a hypothesis should take, it’s best not to be too fancy or complicated; an inventive style isn’t nearly so important as clarity here. There’s nothing wrong with beginning your hypothesis with the phrase, “It was hypothesized that . . .” Be as specific as you can about the relationship between the different objects of your study. In other words, explain that when term A changes, term B changes in this particular way. Readers of scientific writing are rarely content with the idea that a relationship between two terms exists—they want to know what that relationship entails.

Not a hypothesis:

“It was hypothesized that there is a significant relationship between the temperature of a solvent and the rate at which a solute dissolves.”

Hypothesis:

“It was hypothesized that as the temperature of a solvent increases, the rate at which a solute will dissolve in that solvent increases.”

Put more technically, most hypotheses contain both an independent and a dependent variable. The independent variable is what you manipulate to test the reaction; the dependent variable is what changes as a result of your manipulation. In the example above, the independent variable is the temperature of the solvent, and the dependent variable is the rate of solubility. Be sure that your hypothesis includes both variables.

Justify your hypothesis

You need to do more than tell your readers what your hypothesis is; you also need to assure them that this hypothesis was reasonable, given the circumstances. In other words, use the Introduction to explain that you didn’t just pluck your hypothesis out of thin air. (If you did pluck it out of thin air, your problems with your report will probably extend beyond using the appropriate format.) If you posit that a particular relationship exists between the independent and the dependent variable, what led you to believe your “guess” might be supported by evidence?

Scientists often refer to this type of justification as “motivating” the hypothesis, in the sense that something propelled them to make that prediction. Often, motivation includes what we already know—or rather, what scientists generally accept as true (see “Background/previous research” below). But you can also motivate your hypothesis by relying on logic or on your own observations. If you’re trying to decide which solutes will dissolve more rapidly in a solvent at increased temperatures, you might remember that some solids are meant to dissolve in hot water (e.g., bouillon cubes) and some are used for a function precisely because they withstand higher temperatures (they make saucepans out of something). Or you can think about whether you’ve noticed sugar dissolving more rapidly in your glass of iced tea or in your cup of coffee. Even such basic, outside-the-lab observations can help you justify your hypothesis as reasonable.

Background/previous research

This part of the Introduction demonstrates to the reader your awareness of how you’re building on other scientists’ work. If you think of the scientific community as engaging in a series of conversations about various topics, then you’ll recognize that the relevant background material will alert the reader to which conversation you want to enter.

Generally speaking, authors writing journal articles use the background for slightly different purposes than do students completing assignments. Because readers of academic journals tend to be professionals in the field, authors explain the background in order to permit readers to evaluate the study’s pertinence for their own work. You, on the other hand, write toward a much narrower audience—your peers in the course or your lab instructor—and so you must demonstrate that you understand the context for the (presumably assigned) experiment or study you’ve completed. For example, if your professor has been talking about polarity during lectures, and you’re doing a solubility experiment, you might try to connect the polarity of a solid to its relative solubility in certain solvents. In any event, both professional researchers and undergraduates need to connect the background material overtly to their own work.

Organization of this section

Most of the time, writers begin by stating the purpose or objectives of their own work, which establishes for the reader’s benefit the “nature and scope of the problem investigated” (Day 1994). Once you have expressed your purpose, you should then find it easier to move from the general purpose, to relevant material on the subject, to your hypothesis. In abbreviated form, an Introduction section might look like this:

“The purpose of the experiment was to test conventional ideas about solubility in the laboratory [purpose] . . . According to Whitecoat and Labrat (1999), at higher temperatures the molecules of solvents move more quickly . . . We know from the class lecture that molecules moving at higher rates of speed collide with one another more often and thus break down more easily [background material/motivation] . . . Thus, it was hypothesized that as the temperature of a solvent increases, the rate at which a solute will dissolve in that solvent increases [hypothesis].”

Again—these are guidelines, not commandments. Some writers and readers prefer different structures for the Introduction. The one above merely illustrates a common approach to organizing material.

How do I write a strong Materials and Methods section?

As with any piece of writing, your Methods section will succeed only if it fulfills its readers’ expectations, so you need to be clear in your own mind about the purpose of this section. Let’s review the purpose as we described it above: in this section, you want to describe in detail how you tested the hypothesis you developed and also to clarify the rationale for your procedure. In science, it’s not sufficient merely to design and carry out an experiment. Ultimately, others must be able to verify your findings, so your experiment must be reproducible, to the extent that other researchers can follow the same procedure and obtain the same (or similar) results.

Here’s a real-world example of the importance of reproducibility. In 1989, physicists Stanley Pons and Martin Fleischman announced that they had discovered “cold fusion,” a way of producing excess heat and power without the nuclear radiation that accompanies “hot fusion.” Such a discovery could have great ramifications for the industrial production of energy, so these findings created a great deal of interest. When other scientists tried to duplicate the experiment, however, they didn’t achieve the same results, and as a result many wrote off the conclusions as unjustified (or worse, a hoax). To this day, the viability of cold fusion is debated within the scientific community, even though an increasing number of researchers believe it possible. So when you write your Methods section, keep in mind that you need to describe your experiment well enough to allow others to replicate it exactly.

With these goals in mind, let’s consider how to write an effective Methods section in terms of content, structure, and style.

Sometimes the hardest thing about writing this section isn’t what you should talk about, but what you shouldn’t talk about. Writers often want to include the results of their experiment, because they measured and recorded the results during the course of the experiment. But such data should be reserved for the Results section. In the Methods section, you can write that you recorded the results, or how you recorded the results (e.g., in a table), but you shouldn’t write what the results were—not yet. Here, you’re merely stating exactly how you went about testing your hypothesis. As you draft your Methods section, ask yourself the following questions:

  • How much detail? Be precise in providing details, but stay relevant. Ask yourself, “Would it make any difference if this piece were a different size or made from a different material?” If not, you probably don’t need to get too specific. If so, you should give as many details as necessary to prevent this experiment from going awry if someone else tries to carry it out. Probably the most crucial detail is measurement; you should always quantify anything you can, such as time elapsed, temperature, mass, volume, etc.
  • Rationale: Be sure that as you’re relating your actions during the experiment, you explain your rationale for the protocol you developed. If you capped a test tube immediately after adding a solute to a solvent, why did you do that? (That’s really two questions: why did you cap it, and why did you cap it immediately?) In a professional setting, writers provide their rationale as a way to explain their thinking to potential critics. On one hand, of course, that’s your motivation for talking about protocol, too. On the other hand, since in practical terms you’re also writing to your teacher (who’s seeking to evaluate how well you comprehend the principles of the experiment), explaining the rationale indicates that you understand the reasons for conducting the experiment in that way, and that you’re not just following orders. Critical thinking is crucial—robots don’t make good scientists.
  • Control: Most experiments will include a control, which is a means of comparing experimental results. (Sometimes you’ll need to have more than one control, depending on the number of hypotheses you want to test.) The control is exactly the same as the other items you’re testing, except that you don’t manipulate the independent variable-the condition you’re altering to check the effect on the dependent variable. For example, if you’re testing solubility rates at increased temperatures, your control would be a solution that you didn’t heat at all; that way, you’ll see how quickly the solute dissolves “naturally” (i.e., without manipulation), and you’ll have a point of reference against which to compare the solutions you did heat.

Describe the control in the Methods section. Two things are especially important in writing about the control: identify the control as a control, and explain what you’re controlling for. Here is an example:

“As a control for the temperature change, we placed the same amount of solute in the same amount of solvent, and let the solution stand for five minutes without heating it.”

Structure and style

Organization is especially important in the Methods section of a lab report because readers must understand your experimental procedure completely. Many writers are surprised by the difficulty of conveying what they did during the experiment, since after all they’re only reporting an event, but it’s often tricky to present this information in a coherent way. There’s a fairly standard structure you can use to guide you, and following the conventions for style can help clarify your points.

  • Subsections: Occasionally, researchers use subsections to report their procedure when the following circumstances apply: 1) if they’ve used a great many materials; 2) if the procedure is unusually complicated; 3) if they’ve developed a procedure that won’t be familiar to many of their readers. Because these conditions rarely apply to the experiments you’ll perform in class, most undergraduate lab reports won’t require you to use subsections. In fact, many guides to writing lab reports suggest that you try to limit your Methods section to a single paragraph.
  • Narrative structure: Think of this section as telling a story about a group of people and the experiment they performed. Describe what you did in the order in which you did it. You may have heard the old joke centered on the line, “Disconnect the red wire, but only after disconnecting the green wire,” where the person reading the directions blows everything to kingdom come because the directions weren’t in order. We’re used to reading about events chronologically, and so your readers will generally understand what you did if you present that information in the same way. Also, since the Methods section does generally appear as a narrative (story), you want to avoid the “recipe” approach: “First, take a clean, dry 100 ml test tube from the rack. Next, add 50 ml of distilled water.” You should be reporting what did happen, not telling the reader how to perform the experiment: “50 ml of distilled water was poured into a clean, dry 100 ml test tube.” Hint: most of the time, the recipe approach comes from copying down the steps of the procedure from your lab manual, so you may want to draft the Methods section initially without consulting your manual. Later, of course, you can go back and fill in any part of the procedure you inadvertently overlooked.
  • Past tense: Remember that you’re describing what happened, so you should use past tense to refer to everything you did during the experiment. Writers are often tempted to use the imperative (“Add 5 g of the solid to the solution”) because that’s how their lab manuals are worded; less frequently, they use present tense (“5 g of the solid are added to the solution”). Instead, remember that you’re talking about an event which happened at a particular time in the past, and which has already ended by the time you start writing, so simple past tense will be appropriate in this section (“5 g of the solid were added to the solution” or “We added 5 g of the solid to the solution”).
  • Active: We heated the solution to 80°C. (The subject, “we,” performs the action, heating.)
  • Passive: The solution was heated to 80°C. (The subject, “solution,” doesn’t do the heating–it is acted upon, not acting.)

Increasingly, especially in the social sciences, using first person and active voice is acceptable in scientific reports. Most readers find that this style of writing conveys information more clearly and concisely. This rhetorical choice thus brings two scientific values into conflict: objectivity versus clarity. Since the scientific community hasn’t reached a consensus about which style it prefers, you may want to ask your lab instructor.

How do I write a strong Results section?

Here’s a paradox for you. The Results section is often both the shortest (yay!) and most important (uh-oh!) part of your report. Your Materials and Methods section shows how you obtained the results, and your Discussion section explores the significance of the results, so clearly the Results section forms the backbone of the lab report. This section provides the most critical information about your experiment: the data that allow you to discuss how your hypothesis was or wasn’t supported. But it doesn’t provide anything else, which explains why this section is generally shorter than the others.

Before you write this section, look at all the data you collected to figure out what relates significantly to your hypothesis. You’ll want to highlight this material in your Results section. Resist the urge to include every bit of data you collected, since perhaps not all are relevant. Also, don’t try to draw conclusions about the results—save them for the Discussion section. In this section, you’re reporting facts. Nothing your readers can dispute should appear in the Results section.

Most Results sections feature three distinct parts: text, tables, and figures. Let’s consider each part one at a time.

This should be a short paragraph, generally just a few lines, that describes the results you obtained from your experiment. In a relatively simple experiment, one that doesn’t produce a lot of data for you to repeat, the text can represent the entire Results section. Don’t feel that you need to include lots of extraneous detail to compensate for a short (but effective) text; your readers appreciate discrimination more than your ability to recite facts. In a more complex experiment, you may want to use tables and/or figures to help guide your readers toward the most important information you gathered. In that event, you’ll need to refer to each table or figure directly, where appropriate:

“Table 1 lists the rates of solubility for each substance”

“Solubility increased as the temperature of the solution increased (see Figure 1).”

If you do use tables or figures, make sure that you don’t present the same material in both the text and the tables/figures, since in essence you’ll just repeat yourself, probably annoying your readers with the redundancy of your statements.

Feel free to describe trends that emerge as you examine the data. Although identifying trends requires some judgment on your part and so may not feel like factual reporting, no one can deny that these trends do exist, and so they properly belong in the Results section. Example:

“Heating the solution increased the rate of solubility of polar solids by 45% but had no effect on the rate of solubility in solutions containing non-polar solids.”

This point isn’t debatable—you’re just pointing out what the data show.

As in the Materials and Methods section, you want to refer to your data in the past tense, because the events you recorded have already occurred and have finished occurring. In the example above, note the use of “increased” and “had,” rather than “increases” and “has.” (You don’t know from your experiment that heating always increases the solubility of polar solids, but it did that time.)

You shouldn’t put information in the table that also appears in the text. You also shouldn’t use a table to present irrelevant data, just to show you did collect these data during the experiment. Tables are good for some purposes and situations, but not others, so whether and how you’ll use tables depends upon what you need them to accomplish.

Tables are useful ways to show variation in data, but not to present a great deal of unchanging measurements. If you’re dealing with a scientific phenomenon that occurs only within a certain range of temperatures, for example, you don’t need to use a table to show that the phenomenon didn’t occur at any of the other temperatures. How useful is this table?

A table labeled Effect of Temperature on Rate of Solubility with temperature of solvent values in 10-degree increments from -20 degrees Celsius to 80 degrees Celsius that does not show a corresponding rate of solubility value until 50 degrees Celsius.

As you can probably see, no solubility was observed until the trial temperature reached 50°C, a fact that the text part of the Results section could easily convey. The table could then be limited to what happened at 50°C and higher, thus better illustrating the differences in solubility rates when solubility did occur.

As a rule, try not to use a table to describe any experimental event you can cover in one sentence of text. Here’s an example of an unnecessary table from How to Write and Publish a Scientific Paper , by Robert A. Day:

A table labeled Oxygen requirements of various species of Streptomyces showing the names of organisms and two columns that indicate growth under aerobic conditions and growth under anaerobic conditions with a plus or minus symbol for each organism in the growth columns to indicate value.

As Day notes, all the information in this table can be summarized in one sentence: “S. griseus, S. coelicolor, S. everycolor, and S. rainbowenski grew under aerobic conditions, whereas S. nocolor and S. greenicus required anaerobic conditions.” Most readers won’t find the table clearer than that one sentence.

When you do have reason to tabulate material, pay attention to the clarity and readability of the format you use. Here are a few tips:

  • Number your table. Then, when you refer to the table in the text, use that number to tell your readers which table they can review to clarify the material.
  • Give your table a title. This title should be descriptive enough to communicate the contents of the table, but not so long that it becomes difficult to follow. The titles in the sample tables above are acceptable.
  • Arrange your table so that readers read vertically, not horizontally. For the most part, this rule means that you should construct your table so that like elements read down, not across. Think about what you want your readers to compare, and put that information in the column (up and down) rather than in the row (across). Usually, the point of comparison will be the numerical data you collect, so especially make sure you have columns of numbers, not rows.Here’s an example of how drastically this decision affects the readability of your table (from A Short Guide to Writing about Chemistry , by Herbert Beall and John Trimbur). Look at this table, which presents the relevant data in horizontal rows:

A table labeled Boyle's Law Experiment: Measuring Volume as a Function of Pressure that presents the trial number, length of air sample in millimeters, and height difference in inches of mercury, each of which is presented in rows horizontally.

It’s a little tough to see the trends that the author presumably wants to present in this table. Compare this table, in which the data appear vertically:

A table labeled Boyle's Law Experiment: Measuring Volume as a Function of Pressure that presents the trial number, length of air sample in millimeters, and height difference in inches of mercury, each of which is presented in columns vertically.

The second table shows how putting like elements in a vertical column makes for easier reading. In this case, the like elements are the measurements of length and height, over five trials–not, as in the first table, the length and height measurements for each trial.

  • Make sure to include units of measurement in the tables. Readers might be able to guess that you measured something in millimeters, but don’t make them try.
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  • Don’t use vertical lines as part of the format for your table. This convention exists because journals prefer not to have to reproduce these lines because the tables then become more expensive to print. Even though it’s fairly unlikely that you’ll be sending your Biology 11 lab report to Science for publication, your readers still have this expectation. Consequently, if you use the table-drawing option in your word-processing software, choose the option that doesn’t rely on a “grid” format (which includes vertical lines).

How do I include figures in my report?

Although tables can be useful ways of showing trends in the results you obtained, figures (i.e., illustrations) can do an even better job of emphasizing such trends. Lab report writers often use graphic representations of the data they collected to provide their readers with a literal picture of how the experiment went.

When should you use a figure?

Remember the circumstances under which you don’t need a table: when you don’t have a great deal of data or when the data you have don’t vary a lot. Under the same conditions, you would probably forgo the figure as well, since the figure would be unlikely to provide your readers with an additional perspective. Scientists really don’t like their time wasted, so they tend not to respond favorably to redundancy.

If you’re trying to decide between using a table and creating a figure to present your material, consider the following a rule of thumb. The strength of a table lies in its ability to supply large amounts of exact data, whereas the strength of a figure is its dramatic illustration of important trends within the experiment. If you feel that your readers won’t get the full impact of the results you obtained just by looking at the numbers, then a figure might be appropriate.

Of course, an undergraduate class may expect you to create a figure for your lab experiment, if only to make sure that you can do so effectively. If this is the case, then don’t worry about whether to use figures or not—concentrate instead on how best to accomplish your task.

Figures can include maps, photographs, pen-and-ink drawings, flow charts, bar graphs, and section graphs (“pie charts”). But the most common figure by far, especially for undergraduates, is the line graph, so we’ll focus on that type in this handout.

At the undergraduate level, you can often draw and label your graphs by hand, provided that the result is clear, legible, and drawn to scale. Computer technology has, however, made creating line graphs a lot easier. Most word-processing software has a number of functions for transferring data into graph form; many scientists have found Microsoft Excel, for example, a helpful tool in graphing results. If you plan on pursuing a career in the sciences, it may be well worth your while to learn to use a similar program.

Computers can’t, however, decide for you how your graph really works; you have to know how to design your graph to meet your readers’ expectations. Here are some of these expectations:

  • Keep it as simple as possible. You may be tempted to signal the complexity of the information you gathered by trying to design a graph that accounts for that complexity. But remember the purpose of your graph: to dramatize your results in a manner that’s easy to see and grasp. Try not to make the reader stare at the graph for a half hour to find the important line among the mass of other lines. For maximum effectiveness, limit yourself to three to five lines per graph; if you have more data to demonstrate, use a set of graphs to account for it, rather than trying to cram it all into a single figure.
  • Plot the independent variable on the horizontal (x) axis and the dependent variable on the vertical (y) axis. Remember that the independent variable is the condition that you manipulated during the experiment and the dependent variable is the condition that you measured to see if it changed along with the independent variable. Placing the variables along their respective axes is mostly just a convention, but since your readers are accustomed to viewing graphs in this way, you’re better off not challenging the convention in your report.
  • Label each axis carefully, and be especially careful to include units of measure. You need to make sure that your readers understand perfectly well what your graph indicates.
  • Number and title your graphs. As with tables, the title of the graph should be informative but concise, and you should refer to your graph by number in the text (e.g., “Figure 1 shows the increase in the solubility rate as a function of temperature”).
  • Many editors of professional scientific journals prefer that writers distinguish the lines in their graphs by attaching a symbol to them, usually a geometric shape (triangle, square, etc.), and using that symbol throughout the curve of the line. Generally, readers have a hard time distinguishing dotted lines from dot-dash lines from straight lines, so you should consider staying away from this system. Editors don’t usually like different-colored lines within a graph because colors are difficult and expensive to reproduce; colors may, however, be great for your purposes, as long as you’re not planning to submit your paper to Nature. Use your discretion—try to employ whichever technique dramatizes the results most effectively.
  • Try to gather data at regular intervals, so the plot points on your graph aren’t too far apart. You can’t be sure of the arc you should draw between the plot points if the points are located at the far corners of the graph; over a fifteen-minute interval, perhaps the change occurred in the first or last thirty seconds of that period (in which case your straight-line connection between the points is misleading).
  • If you’re worried that you didn’t collect data at sufficiently regular intervals during your experiment, go ahead and connect the points with a straight line, but you may want to examine this problem as part of your Discussion section.
  • Make your graph large enough so that everything is legible and clearly demarcated, but not so large that it either overwhelms the rest of the Results section or provides a far greater range than you need to illustrate your point. If, for example, the seedlings of your plant grew only 15 mm during the trial, you don’t need to construct a graph that accounts for 100 mm of growth. The lines in your graph should more or less fill the space created by the axes; if you see that your data is confined to the lower left portion of the graph, you should probably re-adjust your scale.
  • If you create a set of graphs, make them the same size and format, including all the verbal and visual codes (captions, symbols, scale, etc.). You want to be as consistent as possible in your illustrations, so that your readers can easily make the comparisons you’re trying to get them to see.

How do I write a strong Discussion section?

The discussion section is probably the least formalized part of the report, in that you can’t really apply the same structure to every type of experiment. In simple terms, here you tell your readers what to make of the Results you obtained. If you have done the Results part well, your readers should already recognize the trends in the data and have a fairly clear idea of whether your hypothesis was supported. Because the Results can seem so self-explanatory, many students find it difficult to know what material to add in this last section.

Basically, the Discussion contains several parts, in no particular order, but roughly moving from specific (i.e., related to your experiment only) to general (how your findings fit in the larger scientific community). In this section, you will, as a rule, need to:

Explain whether the data support your hypothesis

  • Acknowledge any anomalous data or deviations from what you expected

Derive conclusions, based on your findings, about the process you’re studying

  • Relate your findings to earlier work in the same area (if you can)

Explore the theoretical and/or practical implications of your findings

Let’s look at some dos and don’ts for each of these objectives.

This statement is usually a good way to begin the Discussion, since you can’t effectively speak about the larger scientific value of your study until you’ve figured out the particulars of this experiment. You might begin this part of the Discussion by explicitly stating the relationships or correlations your data indicate between the independent and dependent variables. Then you can show more clearly why you believe your hypothesis was or was not supported. For example, if you tested solubility at various temperatures, you could start this section by noting that the rates of solubility increased as the temperature increased. If your initial hypothesis surmised that temperature change would not affect solubility, you would then say something like,

“The hypothesis that temperature change would not affect solubility was not supported by the data.”

Note: Students tend to view labs as practical tests of undeniable scientific truths. As a result, you may want to say that the hypothesis was “proved” or “disproved” or that it was “correct” or “incorrect.” These terms, however, reflect a degree of certainty that you as a scientist aren’t supposed to have. Remember, you’re testing a theory with a procedure that lasts only a few hours and relies on only a few trials, which severely compromises your ability to be sure about the “truth” you see. Words like “supported,” “indicated,” and “suggested” are more acceptable ways to evaluate your hypothesis.

Also, recognize that saying whether the data supported your hypothesis or not involves making a claim to be defended. As such, you need to show the readers that this claim is warranted by the evidence. Make sure that you’re very explicit about the relationship between the evidence and the conclusions you draw from it. This process is difficult for many writers because we don’t often justify conclusions in our regular lives. For example, you might nudge your friend at a party and whisper, “That guy’s drunk,” and once your friend lays eyes on the person in question, she might readily agree. In a scientific paper, by contrast, you would need to defend your claim more thoroughly by pointing to data such as slurred words, unsteady gait, and the lampshade-as-hat. In addition to pointing out these details, you would also need to show how (according to previous studies) these signs are consistent with inebriation, especially if they occur in conjunction with one another. To put it another way, tell your readers exactly how you got from point A (was the hypothesis supported?) to point B (yes/no).

Acknowledge any anomalous data, or deviations from what you expected

You need to take these exceptions and divergences into account, so that you qualify your conclusions sufficiently. For obvious reasons, your readers will doubt your authority if you (deliberately or inadvertently) overlook a key piece of data that doesn’t square with your perspective on what occurred. In a more philosophical sense, once you’ve ignored evidence that contradicts your claims, you’ve departed from the scientific method. The urge to “tidy up” the experiment is often strong, but if you give in to it you’re no longer performing good science.

Sometimes after you’ve performed a study or experiment, you realize that some part of the methods you used to test your hypothesis was flawed. In that case, it’s OK to suggest that if you had the chance to conduct your test again, you might change the design in this or that specific way in order to avoid such and such a problem. The key to making this approach work, though, is to be very precise about the weakness in your experiment, why and how you think that weakness might have affected your data, and how you would alter your protocol to eliminate—or limit the effects of—that weakness. Often, inexperienced researchers and writers feel the need to account for “wrong” data (remember, there’s no such animal), and so they speculate wildly about what might have screwed things up. These speculations include such factors as the unusually hot temperature in the room, or the possibility that their lab partners read the meters wrong, or the potentially defective equipment. These explanations are what scientists call “cop-outs,” or “lame”; don’t indicate that the experiment had a weakness unless you’re fairly certain that a) it really occurred and b) you can explain reasonably well how that weakness affected your results.

If, for example, your hypothesis dealt with the changes in solubility at different temperatures, then try to figure out what you can rationally say about the process of solubility more generally. If you’re doing an undergraduate lab, chances are that the lab will connect in some way to the material you’ve been covering either in lecture or in your reading, so you might choose to return to these resources as a way to help you think clearly about the process as a whole.

This part of the Discussion section is another place where you need to make sure that you’re not overreaching. Again, nothing you’ve found in one study would remotely allow you to claim that you now “know” something, or that something isn’t “true,” or that your experiment “confirmed” some principle or other. Hesitate before you go out on a limb—it’s dangerous! Use less absolutely conclusive language, including such words as “suggest,” “indicate,” “correspond,” “possibly,” “challenge,” etc.

Relate your findings to previous work in the field (if possible)

We’ve been talking about how to show that you belong in a particular community (such as biologists or anthropologists) by writing within conventions that they recognize and accept. Another is to try to identify a conversation going on among members of that community, and use your work to contribute to that conversation. In a larger philosophical sense, scientists can’t fully understand the value of their research unless they have some sense of the context that provoked and nourished it. That is, you have to recognize what’s new about your project (potentially, anyway) and how it benefits the wider body of scientific knowledge. On a more pragmatic level, especially for undergraduates, connecting your lab work to previous research will demonstrate to the TA that you see the big picture. You have an opportunity, in the Discussion section, to distinguish yourself from the students in your class who aren’t thinking beyond the barest facts of the study. Capitalize on this opportunity by putting your own work in context.

If you’re just beginning to work in the natural sciences (as a first-year biology or chemistry student, say), most likely the work you’ll be doing has already been performed and re-performed to a satisfactory degree. Hence, you could probably point to a similar experiment or study and compare/contrast your results and conclusions. More advanced work may deal with an issue that is somewhat less “resolved,” and so previous research may take the form of an ongoing debate, and you can use your own work to weigh in on that debate. If, for example, researchers are hotly disputing the value of herbal remedies for the common cold, and the results of your study suggest that Echinacea diminishes the symptoms but not the actual presence of the cold, then you might want to take some time in the Discussion section to recapitulate the specifics of the dispute as it relates to Echinacea as an herbal remedy. (Consider that you have probably already written in the Introduction about this debate as background research.)

This information is often the best way to end your Discussion (and, for all intents and purposes, the report). In argumentative writing generally, you want to use your closing words to convey the main point of your writing. This main point can be primarily theoretical (“Now that you understand this information, you’re in a better position to understand this larger issue”) or primarily practical (“You can use this information to take such and such an action”). In either case, the concluding statements help the reader to comprehend the significance of your project and your decision to write about it.

Since a lab report is argumentative—after all, you’re investigating a claim, and judging the legitimacy of that claim by generating and collecting evidence—it’s often a good idea to end your report with the same technique for establishing your main point. If you want to go the theoretical route, you might talk about the consequences your study has for the field or phenomenon you’re investigating. To return to the examples regarding solubility, you could end by reflecting on what your work on solubility as a function of temperature tells us (potentially) about solubility in general. (Some folks consider this type of exploration “pure” as opposed to “applied” science, although these labels can be problematic.) If you want to go the practical route, you could end by speculating about the medical, institutional, or commercial implications of your findings—in other words, answer the question, “What can this study help people to do?” In either case, you’re going to make your readers’ experience more satisfying, by helping them see why they spent their time learning what you had to teach them.

Works consulted

We consulted these works while writing this handout. This is not a comprehensive list of resources on the handout’s topic, and we encourage you to do your own research to find additional publications. Please do not use this list as a model for the format of your own reference list, as it may not match the citation style you are using. For guidance on formatting citations, please see the UNC Libraries citation tutorial . We revise these tips periodically and welcome feedback.

American Psychological Association. 2010. Publication Manual of the American Psychological Association . 6th ed. Washington, DC: American Psychological Association.

Beall, Herbert, and John Trimbur. 2001. A Short Guide to Writing About Chemistry , 2nd ed. New York: Longman.

Blum, Deborah, and Mary Knudson. 1997. A Field Guide for Science Writers: The Official Guide of the National Association of Science Writers . New York: Oxford University Press.

Booth, Wayne C., Gregory G. Colomb, Joseph M. Williams, Joseph Bizup, and William T. FitzGerald. 2016. The Craft of Research , 4th ed. Chicago: University of Chicago Press.

Briscoe, Mary Helen. 1996. Preparing Scientific Illustrations: A Guide to Better Posters, Presentations, and Publications , 2nd ed. New York: Springer-Verlag.

Council of Science Editors. 2014. Scientific Style and Format: The CSE Manual for Authors, Editors, and Publishers , 8th ed. Chicago & London: University of Chicago Press.

Davis, Martha. 2012. Scientific Papers and Presentations , 3rd ed. London: Academic Press.

Day, Robert A. 1994. How to Write and Publish a Scientific Paper , 4th ed. Phoenix: Oryx Press.

Porush, David. 1995. A Short Guide to Writing About Science . New York: Longman.

Williams, Joseph, and Joseph Bizup. 2017. Style: Lessons in Clarity and Grace , 12th ed. Boston: Pearson.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

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Complete Guide to Writing a Lab Report (With Example)

Students tend to approach writing lab reports with confusion and dread. Whether in high school science classes or undergraduate laboratories, experiments are always fun and games until the times comes to submit a lab report. What if we didn’t need to spend hours agonizing over this piece of scientific writing? Our lives would be so much easier if we were told what information to include, what to do with all their data and how to use references. Well, here’s a guide to all the core components in a well-written lab report, complete with an example.

Things to Include in a Laboratory Report

The laboratory report is simply a way to show that you understand the link between theory and practice while communicating through clear and concise writing. As with all forms of writing, it’s not the report’s length that matters, but the quality of the information conveyed within. This article outlines the important bits that go into writing a lab report (title, abstract, introduction, method, results, discussion, conclusion, reference). At the end is an example report of reducing sugar analysis with Benedict’s reagent.

The report’s title should be short but descriptive, indicating the qualitative or quantitative nature of the practical along with the primary goal or area of focus.

Following this should be the abstract, 2-3 sentences summarizing the practical. The abstract shows the reader the main results of the practical and helps them decide quickly whether the rest of the report is relevant to their use. Remember that the whole report should be written in a passive voice .

Introduction

The introduction provides context to the experiment in a couple of paragraphs and relevant diagrams. While a short preamble outlining the history of the techniques or materials used in the practical is appropriate, the bulk of the introduction should outline the experiment’s goals, creating a logical flow to the next section.

Some reports require you to write down the materials used, which can be combined with this section. The example below does not include a list of materials used. If unclear, it is best to check with your teacher or demonstrator before writing your lab report from scratch.

Step-by-step methods are usually provided in high school and undergraduate laboratory practicals, so it’s just a matter of paraphrasing them. This is usually the section that teachers and demonstrators care the least about. Any unexpected changes to the experimental setup or techniques can also be documented here.

The results section should include the raw data that has been collected in the experiment as well as calculations that are performed. It is usually appropriate to include diagrams; depending on the experiment, these can range from scatter plots to chromatograms.

The discussion is the most critical part of the lab report as it is a chance for you to show that you have a deep understanding of the practical and the theory behind it. Teachers and lecturers tend to give this section the most weightage when marking the report. It would help if you used the discussion section to address several points:

  • Explain the results gathered. Is there a particular trend? Do the results support the theory behind the experiment?
  • Highlight any unexpected results or outlying data points. What are possible sources of error?
  • Address the weaknesses of the experiment. Refer to the materials and methods used to identify improvements that would yield better results (more accurate equipment, better experimental technique, etc.)  

Finally, a short paragraph to conclude the laboratory report. It should summarize the findings and provide an objective review of the experiment.

If any external sources were used in writing the lab report, they should go here. Referencing is critical in scientific writing; it’s like giving a shout out (known as a citation) to the original provider of the information. It is good practice to have at least one source referenced, either from researching the context behind the experiment, best practices for the method used or similar industry standards.

Google Scholar is a good resource for quickly gathering references of a specific style . Searching for the article in the search bar and clicking on the ‘cite’ button opens a pop-up that allows you to copy and paste from several common referencing styles.

referencing styles from google scholar

Example: Writing a Lab Report

Title : Semi-Quantitative Analysis of Food Products using Benedict’s Reagent

Abstract : Food products (milk, chicken, bread, orange juice) were solubilized and tested for reducing sugars using Benedict’s reagent. Milk contained the highest level of reducing sugars at ~2%, while chicken contained almost no reducing sugars.

Introduction : Sugar detection has been of interest for over 100 years, with the first test for glucose using copper sulfate developed by German chemist Karl Trommer in 1841. It was used to test the urine of diabetics, where sugar was present in high amounts. However, it wasn’t until 1907 when the method was perfected by Stanley Benedict, using sodium citrate and sodium carbonate to stabilize the copper sulfate in solution. Benedict’s reagent is a bright blue because of the copper sulfate, turning green and then red as the concentration of reducing sugars increases.

Benedict’s reagent was used in this experiment to compare the amount of reducing sugars between four food items: milk, chicken solution, bread and orange juice. Following this, standardized glucose solutions (0.0%, 0.5%, 1.0%, 1.5%, 2.0%) were tested with Benedict’s reagent to determine the color produced at those sugar levels, allowing us to perform a semi-quantitative analysis of the food items.

Method : Benedict’s reagent was prepared by mixing 1.73 g of copper (II) sulfate pentahydrate, 17.30 g of sodium citrate pentahydrate and 10.00 g of sodium carbonate anhydrous. The mixture was dissolved with stirring and made up to 100 ml using distilled water before filtration using filter paper and a funnel to remove any impurities.

4 ml of milk, chicken solution and orange juice (commercially available) were measured in test tubes, along with 4 ml of bread solution. The bread solution was prepared using 4 g of dried bread ground with mortar and pestle before diluting with distilled water up to 4 ml. Then, 4 ml of Benedict’s reagent was added to each test tube and placed in a boiling water bath for 5 minutes, then each test tube was observed.

Next, glucose solutions were prepared by dissolving 0.5 g, 1.0 g, 1.5 g and 2.0 g of glucose in 100 ml of distilled water to produce 0.5%, 1.0%, 1.5% and 2.0% solutions, respectively. 4 ml of each solution was added to 4 ml of Benedict’s reagent in a test tube and placed in a boiling water bath for 5 minutes, then each test tube was observed.

Results : Food Solutions (4 ml) with Benedict’s Reagent (4 ml)

Food SolutionsColor Observed
MilkRed
Chicken SolutionBlue
BreadGreen
Orange JuiceOrange

Glucose Solutions (4 ml) with Benedict’s Reagent (4 ml)

Glucose SolutionsColor Observed
0.0% (Control)Blue
0.5%Green
1.0%Dark Green
1.5%Orange
2.0%Red

Semi-Quantitative Analysis from Data

Food SolutionsSugar Levels
Milk2.0%
Chicken Solution0.0%
Bread0.5%
Orange Juice1.5%

Discussion : From the analysis of food solutions along with the glucose solutions of known concentrations, the semi-quantitative analysis of sugar levels in different food products was performed. Milk had the highest sugar content of 2%, with orange juice at 1.5%, bread at 0.5% and chicken with 0% sugar. These values were approximated; the standard solutions were not the exact color of the food solutions, but the closest color match was chosen.

One point of contention was using the orange juice solution, which conferred color to the starting solution, rendering it green before the reaction started. This could have led to the final color (and hence, sugar quantity) being inaccurate. Also, since comparing colors using eyesight alone is inaccurate, the experiment could be improved with a colorimeter that can accurately determine the exact wavelength of light absorbed by the solution.

Another downside of Benedict’s reagent is its inability to react with non-reducing sugars. Reducing sugars encompass all sugar types that can be oxidized from aldehydes or ketones into carboxylic acids. This means that all monosaccharides (glucose, fructose, etc.) are reducing sugars, while only select polysaccharides are. Disaccharides like sucrose and trehalose cannot be oxidized, hence are non-reducing and will not react with Benedict’s reagent. Furthermore, Benedict’s reagent cannot distinguish between different types of reducing sugars.

Conclusion : Using Benedict’s reagent, different food products were analyzed semi-quantitatively for their levels of reducing sugars. Milk contained around 2% sugar, while the chicken solution had no sugar. Overall, the experiment was a success, although the accuracy of the results could have been improved with the use of quantitative equipment and methods.

Reference :

  • Raza, S. I., Raza, S. A., Kazmi, M., Khan, S., & Hussain, I. (2021). 100 Years of Glucose Monitoring in Diabetes Management.  Journal of Diabetes Mellitus ,  11 (5), 221-233.
  • Benedict, Stanley R (1909). A Reagent for the Detection of Reducing Sugars.  Journal of Biological Chemistry ,  5 , 485-487.

Using this guide and example, writing a lab report should be a hassle-free, perhaps even enjoyable process!

About the Author

sean author

Sean is a consultant for clients in the pharmaceutical industry and is an associate lecturer at La Trobe University, where unfortunate undergrads are subject to his ramblings on chemistry and pharmacology.

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How to Write the Perfect Chemistry Lab Report: A Definitive Guide

February 11, 2020 By Guest Posts Leave a Comment

Students have to deal with multiple academic tasks, and writing lab reports (lots of them!) is one of them. Its main purpose is to explain what you did in your experiment, what you learned and what the results meant.

Performing experiments and reporting them properly is a cornerstone of on your way into learning chemistry .

But how do you write a chemistry lab report properly?

It’s now time to find out!

writing a chemistry lab report for an experiment

Our ultimate guide sheds light on the main parts of lab report writing. You ought to be aware of every section and understand how to complete them properly. Therefore, we have divided our guide into three major sections that are:

  • Parts of the lab report;
  • A step-by-step review;
  • Writing your project.

General Information

It’s necessary to begin with an overview of the main sections that should be present on a laboratory report for chemistry.

Provides general data about your experiment, including your name, date, the title of the experiment, your teammates (if you have any), the course you are taking, and your instructor’s name. You should leave space for an abstract right after. It’s a couple of paragraphs long section, which briefly states the main purpose of your project. You should write a hypothesis right at the end of your intro. Back up everything with the appropriate references. Make a list of all the materials you’ve used during your experiment. This section highlights your experimental procedures step by step and provides information about the scientific methods you have used to complete the experiment. You should mention all the results you’ve collected during your experiment. Simply record facts but don’t explain them yet. A researcher is supposed to explain all collected data in words. This section serves as the interpreter of the results. You should determine whether you’ve reached your hypothesis or not. Extract conclusions from your data. Summarizes the entire project regardless of the success or failure of your hypothesis and explains it. Represent your dependent and independent variables in the form of graphs and/or tables. For example, you might want to add a representation of the . Enlist the works of other scientists whose studies and articles were used to complete your project.

Mind that sometimes these sections are called differently but have the same purpose. Some of the sections may be missing, but the general structure should be close to this. Everything depends on the educational institution.

It is important to know that usually lab reports are written after the lab session is finished . This means that you need to have everything previously recorded in your lab notebook . You are supposed to keep track of everything you do in the lab in your laboratory notebook, and then using that notebook to write down your lab report, not the other way around.

Reviewing Every Step

Now, we’d like to go through the main stages of a chemistry lab report. It’s necessary to add brief comments concerning each of them. Your laboratory report begins with a title page. You already know what it consists of. Let’s check how to compose it correctly. The information must be presented on the upper right-hand side of the page. All the points (the title, your name, collaborators, etc.) should be mentioned on the separate line.

Afterward comes the second part, which includes:

  • The course title
  • Title of the experiment
  • Title of the parts within the experiment
  • Semester, year, etc. (optional)

This data appears in the middle of the title page.

The next section is the Introduction and it begins with this word in the left upper corner of your report. It should consist of no more than a couple of paragraphs and end with at least one hypothesis.

The body of your project consists of the procedure, materials and methods employed; data; results and observations.  The section Procedure commonly consists of several steps that were followed for the proper conduction of the experiment(s). They could be divided in different parts, and those would describe your actions.

The section Data contains the numerical facts and Observations that provide the changes that took place. Afterwards, you move to the Discussions, in which you ought to plainly explain all the numbers, observations and collected data. Your conclusions provide an overall summary of the entire lab report, and the whole experimental session itself.

Writing a Chemistry Lab Report

The last lap in our “race” is to write a laboratory report . We have already mentioned the main constituents of the title page. Therefore, we can hit the text of your project. Your abstract appears soon after the title page. An abstract is a quick summary that sums up the whole thing (hypothesis to be proven, and conclusions that are reached). Nonetheless, you should leave some space and skip it until the entire project is finished. It is recommended to write the abstract last. The main point is that this section provides a brief review of what your lab report is about and what you’ve managed to achieve.

Main Sections

The introductory part tells your readers what to expect from the project. Write a couple o paragraphs and explain the purpose of your experiment. Including references here is also highly encouraged. The last sentence of your introduction is called a hypothesis or a thesis statement. It shows what you hope to achieve at the end of your research.

The main body consists of several parts and of course, each has its purpose. You should introduce the materials and methods you need to conduct the research. Explain your choice and how your choice helps to conduct a safe and accurate study.

Take instant records of everything that happens during the experiment in your lab notebook . Never rely on your memory!

Afterwards, you’ll interpret the data and explain it using plain words. Don’t draw any conclusions when you record data and don’t explain it in the section called Results. This function should be fulfilled in the sections Discussions or Analysis sections, which should come right afterwards.

Your conclusion makes a brief summary. It should consist of 3-4 sentences, not many more. Restate your hypothesis in other words. Mention whether you’ve achieved your initial goal and explain its value.

Importantly, do realize that if a hypothesis cannot be proven, or an experiment doesn’t give you the results you expected, it doesn’t mean that your experiment and lab session was a failure. It is extremely common in chemistry to find yourself on this kind of situations! You only need to be able to explain why you got the results that you got, and how would you go around to fix them!

Further Sections on Your Report

Don’t forget about the contributors (labmates, supervisiors…) to your research.

You should also obligatorily use some secondary sources to support your theory. Therefore, you have to cite and make references according to the assigned writing format. You can reference other articles all over your manuscript (especially in the introduction and discussion sections), but don’t forget to put them together (or at the bottom of each page), and cite them properly.

The final step is to proofread your lab report. You’re free to use reading aloud and in your head, reading everything again, and using special grammar and spelling checking applications.

To sum up, keep in mind all these guidelines when you’re assigned to write a lab report. Thus, you’ll never miss something important, which can cost you essential grades. Write each section properly to receive the highest grades for your experiment. Always be clear, cite the appropriate references, and be objective with your analysis and conclusions!

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Improving your Title
A good title efficiently tells the reader what the report is about. It may include such information as the subject of the experiment (what it is about), the key research variables, the kind of research methodology used, and the overall findings of the experiment. To make your titles better, follow these guidelines:

Improving your Abstract
A good Abstract is a miniature version of the lab report in one concise paragraph and labeled Abstract.

If you are not sure what should be included in each summary sentence, use the following list as a guide:

If your Abstract is too long, look carefully at each summary sentence and take out any information that is not essential to that section of the report.

Improving your Introduction


To establish the scientific concept for the lab you need to do two things:

1. state what the lab is about, that is, what scientific concept (theory, principle, procedure, etc.) you are supposed to be learning about by doing the lab. You should do this briefly, in a sentence or two. If you are having trouble writing the opening sentence of the report, you can try something like: "This laboratory experiment focuses on X…"; "This lab is designed to help students learn about, observe, or investigate, X…." Or begin with a definition of the scientific concept: "X is a theory that…."

2. give the necessary background for the scientific concept by telling what you know about it (the main references you can use are the lab manual, the textbook, lecture notes, and other sources recommended by the lab manual or lab instructor; in more advanced labs you may also be expected to cite the findings of previous scientific studies related to the lab). In relatively simple labs you can do this in a paragraph following the initial statement of the scientific concept of the lab. But in more complex labs, the background may require more paragraphs.


In a paragraph, or more if you need it, write out the objectives of the lab in paragraph form and then describe the purpose of the lab: what it is that accomplishing the objectives will help you learn about the scientific concept of the lab.

1. The objective(s) are what it is you are supposed to accomplish in the experimental procedure itself. The objective(s), therefore, is usually presented in terms of a specific verb that describes what you are supposed to be doing in the lab, such as to measure, to analyze, to determine, to test etc. Often, the objective(s) for the lab is given in the lab manual. If you are having trouble phrasing the sentence about objectives, try something like: "The main objectives of this lab were to…"; "In this lab we were to…."

2. The purpose of the lab is different in significant ways from its objective(s). Purpose provides the wider view; it answers the why question, why you are doing the lab in the first place. Instead of focusing just on the specific actions of the experimental procedure, purpose looks at the experimental procedure within the context of what you are supposed to be learning.

If you are having trouble starting the sentence about the purpose of the lab, try saying something like this: "The objectives of this lab enabled me to learn about X by…"; "Performing these objectives helped me to understand X by…." To improve this part of the introduction, go back to what you have written about the scientific concept and look for a link between it and the activities you are expected to perform in the lab: what specifically about the scientific concept were these activities designed to teach you?


A good statement of the hypothesis summarizes in a sentence or two what outcomes you anticipate for the experimental procedure. Typically the outcomes will be presented in terms of the relationship between dependent and independent variables. If you are having trouble starting the paragraph on the hypothesis, try a sentence opener like this: "The hypothesis for this lab was…"; "My hypothesis was…"; "We predicted that…"; I hypothesized that…."

Providing logical reasoning for the hypothesis means explaining the reasoning that you used to make your hypothesis. Usually this reasoning is based on what you know about the scientific concept of the lab and how that knowledge led you to the hypothesis. In science, you reason from what you know to what you don't know. In a couple of sentences (more for complex labs) describe the logic that you used to reason from what you know about the scientific concept to your educated guess of the outcomes of the experimental procedure. If you need to make the logic of your hypothesis clearer, use words that indicate an explanation: because, since, due to the fact that, as a result, therefore, consequently, etc.

Often you can present the hypothesis and the supporting reasoning in one paragraph. In more complex labs, especially those with multiple procedures and therefore multiple hypotheses, you may need more paragraphs, perhaps one for each hypothesis.

Improving your Methods

A good Methods section describes what you did in the lab in a way that is easy to understand and detailed enough to be repeated. To make your Methods better, follow these guidelines:

Improving your Results


Results sections typically begin with a brief overview of the findings. This is where you sum up your findings. Such a statement is typically a sentence or two. This summary will act as the opening sentence for the Results. If you had trouble getting the first sentence started, here are some possibilities: "The results of the lab show that …"; "The data from the experiments demonstrate that…"; "The independent variable X increased as Y and Z were…."

One of the main problems with visuals is lack of clarity. You may have chosen a form of visual that does not represent the data clearly. To see if there is a form of visual that represents the data more clearly, go to the LabWrite Graphing Resources for help.

Another problem with visuals can be ascribed to lack of accuracy. Visuals are accurate when they correctly represent the data from the experiment. If there is a problem with accuracy, you should check three points at which accuracy could be jeopardized: (1) you may have recorded the raw data from the procedure incorrectly; (2) you may have entered the raw data onto the spread sheet incorrectly; and (3) you may have made careless errors in the format of the visuals, particularly in labeling the x- and y-axes and in designating the units along those axes.

The presentation of findings in words should be ordered according the order of the visuals, each visual being described in words. Each description should include a sentence or so summarizing the visual and then any details from the visual pertinent to the data from that visual. To make the verbal part of your Results better, follow this general outline:

Etc.

The verbal representation of each visual should refer explicitly to the visual (Table 1, Figure 2, etc.). You should create the sense that the visual and the word representations of data are working together. The primary way of doing that is to cite the visuals in your verbal findings. If you had trouble integrating the verbal and the visuals, be sure you have, at a minimum, a reference to the visual in the first sentence of each paragraph when you describe the overall finding of the visual.

Improving your Discussion

The Discussion should start with a sentence or two in which you make a judgment as to whether your original hypothesis (from the Introduction) was supported, supported with qualifications, or not supported by the findings. To improve the opening of your Introduction, make sure your judgment is stated clearly, so that the reader can understand it. There are, generally speaking, three possible conclusions you could draw:

If you had trouble composing this sentence, try being straightforward about it, for example, "The hypothesis that X solution would increase in viscosity when solutions Y and Z were added was supported by the data."


After stating the judgment about the hypothesis, you should provide specific evidence from the data in the Results to back up the judgment. The first key to improving this part of the Discussion is finding specific evidence reported in the Results that you can use to back up your judgment about your hypothesis. The second key is to describe the evidence in such a way that the reader can clearly see that there is sufficient evidence that supports your judgment about the hypothesis. Be specific. Point out specific evidence from the Results and show how that evidence contributed to your judgment about the hypothesis.


You should return to the scientific concept of the lab (described in the Introduction) and use that concept as a basis for explaining your judgment of the hypothesis. Your understanding of the scientific concept may have changed by doing the lab.

Problems with the sufficiency of the explanation refer to the reader's judgment that you didn't include enough details in your explanation, that there wasn't enough of an explanation to satisfy the reader that you fully understood why the relationship between the results and hypothesis was what it was. You need to provide greater depth in your explanation. Do some brainstorming. Look again at the explanation you placed at the end of the Introduction. Jot down more details about the explanation and use those jottings to help you expand that part of the Discussion.

Problems with the logic of the explanation refer to the reader's judgment that your explanation of the support or lack of support of the hypothesis did not adhere to sound scientific reasoning. Look at the reasoning you used in the explanation. It should follow one of four basic arguments:

1. If the results fully support your hypothesis and your reasoning was basically sound, then elaborate on your reasoning by showing how the science behind the experiment provides an explanation for the results.

2. If the results fully support your hypothesis but your reasoning was not completely sound, then explain why the initial reasoning was not correct and provide the better reasoning.

3. If the results generally support the hypothesis but with qualifications, then describe those qualifications and use your reasoning as a basis for discussing why the qualifications are necessary.

4. If the results do not support your hypothesis, then explain why not; consider (1) problems with your understanding of the lab's scientific concept; (2) problems with your reasoning, and/or (3) problems with the laboratory procedure itself (if there are problems of reliability with the lab data or if you made any changes in the lab procedure, discuss these in detail, showing specifically how they could have affected the results and how the errors could have been eliminated).

You can also improve the logic of your explanation by using words that make your argument clear, such as , , , , , , etc.


A low rating in this area means that the instructor thinks that there are other interesting issues you could have discussed about your findings. Other issues that may be appropriate to address are (1) any problems that occurred or sources of error in your lab procedure that may account for any unexpected results; (2) how your findings compare to the findings of other students in the lab and an explanation for any differences (check with the lab instructor first to make sure this is permissible); (3) suggestions for improving the lab.

Improving your Conclusion

A good Conclusion takes you back to the larger purpose of the lab as stated in the Introduction: to learn something about the scientific concept, the primary reason for doing the lab. The Conclusion is your opportunity to show your lab instructor what you learned by doing lab and writing the lab report.

You can improve your Conclusion first by making a clearer statement of what you learned. Go back to the purpose of the lab as you presented it in your Introduction. You are supposed to learn something about the scientific concept or theory or principle or important scientific procedure that the lab is about. If you are not sure if you have stated what you have learned directly enough, read your first paragraph to see if your reader would have any doubt about what you have learned. If there is any doubt, you may begin the paragraph by saying something like, "In this lab, I learned that ...."

Simply saying you learned something is not necessarily going to convince the reader that you actually did learn it. Demonstrate that you did indeed learn what you claimed to have learned by adding more details to provide an elaboration on the basic statement. Read over the Results and Discussion and jot down some notes for further details on what you have learned. Look carefully at the statement of what you have learned and underline any words or phrases that you could "unpack," explain in more detail. Use this brainstorming as a way of helping you to find details that make your Conclusion more convincing.

If you think you need to do more to convince your reader that you have learned what you say you have learned, provide more details in the Conclusion. For example, compare what you know now with what you knew before doing the lab. Describe specific parts of the procedure or data that contributed to your learning. Discuss how you may be able to apply what you have learned in the lab to other situations in the future.

 

Improving the Presentation of your Report


Different fields tend to have different styles of documentation, that is, the way you cite a source and the way you represent the source in the References. For example, biologists use the documentation style of the Council of Biological Editors, and chemists use the style of the American Chemical Society. If you don't know what style you are expected to use in your reports (it's often given in the lab manual), check with your lab instructor. For further help you can check LabWrite Resources, "Citations and References."


Tables and figures should be done to professional standards, such as proper headings and captions and numbering. For help, go to LabWrite Resource: "Revising your Visuals: Tables, Graphs, and Drawings."

Style in this case refers to your choice of words and sentence structure. The style of science writing strives to be clear and to the point. You should avoid using grand thesaurus words and long, artfully convoluted sentences.

As to choice of words, science writing uses words that its audience (other scientists in the field) will readily understand. To outsiders, the scientific vocabulary of this language looks like a lot of jargon. But the point is that scientific words that are obscure to outsiders are usually not obscure to the insiders that comprise the scientific audience. Your writing should sound like scientific writing. This means that you should go ahead and use proper scientific terminology, but you should also choose plain, everyday words for non-scientific terminology.

Your sentences should be clear and readable for your educated audience. Avoid excessively long and meandering sentences. But don't use a lot of very short sentences, either. Vary your sentence length. If you have difficulties with making your sentences readable, read over them aloud, noting the sentences that seem to be too long or are hard to read. Rewrite those sentences so that they flow more easily.

Also, avoid using quotations. Scientists very rarely quote from source materials; they do so only when a particular wording is important to the point they are trying to make. Using direct quotations is appropriate to English papers, but not to lab reports.

It's important that you understand that the source of grammar problems is not, for most of us, a matter of not knowing the rules of grammar. So don't worry about that. The source of most grammatical errors is simply not seeing them in your own writing. We usually read our own writing for the meaning that the words convey and not for the words themselves.

Correcting grammar problems, then, is usually a matter of learning to read our writing differently. Read your lab report at least twice specifically looking for errors in grammar. You should focus on the words and sentences themselves. You don't need any special knowledge for detecting and correcting most grammar problems. If you do read for error, you will probably be able to spot problems and correct them without having to look anything up in a handbook.

If you feel like you do need special help with grammar, go to the "On-line Writing Handbook" on the LabWrite Resources Page.

First, run the spell-checker on your computer. That should take care of almost all of your spelling problems. Sometimes, however, there are words that the spell-checker does not catch because they are words that are actually spelled correctly but are used for the wrong meaning, like using "to" for "too" and "that" for "than." You should be able to spot these misuses of words by reading over the report looking for error, as described under "grammar errors" immediately above.

 

Overall Aims of the Report: The student...

This is, of course, the purpose for doing the lab, to learn something about the science of the course you are taking. Reading your lab report gives your teacher a good idea of how well you have achieved this all important aim. It's your job in the lab report to represent as fairly as you can what you have learned.

What you have learned is indicated in the report, especially the Introduction and the Conclusion. You can improve the Introduction by (1) expressing more clearly the scientific concept you are supposed to be learning about and (2) showing that you have a good understanding of the scientific concept (see treatment of Introduction above). In addition, check your designation of the purpose of the lab in the Introduction. Be sure that it explicitly and clearly makes the connection between the objectives of the procedure and the scientific concept.

The other key part of the report you should review is the Conclusion. This is where you make your strongest case for what you learned in doing the lab. You may be able to improve the Conclusion by rewriting the statement of what you have learned, revising it so that it is clearer to the reader. You could also enhance the rest of the Conclusion by adding more details concerning what you have learned (see treatment of Conclusion above). Remember, your job is to convince your reader that you have achieved the overall learning goal of the lab, and this is the section of the report in which you do that directly.


One of the objects of the lab and lab report is to give you the experience of participating in scientific inquiry, the form of thinking that defines science. In other words, you need to show through the lab report that you can think like a scientist. There are key places in the report where you indicate your ability to do that.

The first is found at the end of the Introduction where you present your hypothesis, which drives scientific inquiry. You can improve this part of the report by (1) restating the hypothesis so that it more clearly and more specifically presents your educated guess of the outcomes of the experimental procedure and (2) enhancing the logic that you use to show how you have reasoned from what you know about the scientific concept to your hypothesis. You may need to make the links in that logical chain clearer to the reader, or you may need to entirely rethink your reasoning (which could lead to a different hypothesis).

The other place in your report in which you exhibit your ability to think scientifically is in the Discussion. That's where you come back to the hypothesis to see if it is supported or not supported by the results of the procedure. First, are you making a reasonable judgment about whether or not the hypothesis is supported by the findings? Second, do you provide clear evidence from the Results that back up your judgment? And third, do you give a sound explanation, based on your understanding of the scientific concept of the lab, for your judgment? Perhaps you need to revise your explanation so that it is more logical, provides a greater depth of discussion (more details), and treats all the facts that are relevant.

Also in the Discussion you have the opportunity to compare your results to the results of others, other students in the lab or (in more sophisticated labs) published scientific studies. This is an important aspect of scientific inquiry. Look to see that you make the necessary comparisons and that your explanations for the comparisons are full and logical.

There are two ways of looking at this aim, depending on the kind of lab you are in. In some labs, there is a "right answer," a specific unknown or standard measurement you are expected to find. In these cases, the emphasis of the aim is on "expected outcomes." That is, your laboratory procedure is expected to yield certain results and, to a certain extent, the quality of your work depends on whether or not you attain those results.

In other labs, there may be no established outcome for the procedure, or it may be that doing the procedure in a scientifically sound way is more important than the particular answer you get.

In both kinds of labs, the places where you need to focus your efforts on improvement are Methods and Results. If you need to have the right answer, then you should revisit your lab notebook to search out errors in recording data and transcribing data to spreadsheet and in any calculations you have done. You must rewrite your report accordingly.

But if your aim is to demonstrate that your procedures are sound and that they legitimately lead to your results, then look at these sections of the report. Is your procedure described clearly enough? Are your results presented in sufficient detail? The point is to demonstrate that there is a clear relationship between procedure and outcomes.

 

 
   

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Chemistry Lab Resources (for CHM 1XX and 2XX Labs)

  • Organizing Your Lab Notebook
  • Parts of a Lab Report
  • Writing Your Lab Report/Worksheet
  • Graphs/Tables
  • Common Calculations
  • Citing Sources
  • Finding Chemical Properties
  • Lab techniques, instrumentation, and protocols
  • Chemical Safety

General tips

Whether you are filling out lab worksheets or writing up entire lab reports, there are a few tips that will help you to create more detailed and professional documents and to assist in grading:

  • Always label your units
  • Show all of your calculations (don’t leave out steps)
  • Use complete sentences
  • Write neatly
  • Strike out mistakes with a single line
  • Be aware of significant figures, noting the sensitivity of the device you are using for your measurements

Why do we write lab reports in passive voice?

It’s part of the scientific point of view.  We observe and record as objectively as possible, avoiding personal bias by removing ourselves.  Using the passive voice also clarifies procedures and descriptions so they can be easily reproduced and compared.

NOTE: DO NOT write reports as directions, such as those given in your lab manual. For example, do not write, "Heat the solution until it boils." Instead, write "The solution was heated to boiling."

Write in the third person - Scientific experiments demonstrate facts that do not depend on the observer, therefore, reports should avoid using the first and second person (I,me,my,we,our, OR us.)

Using the correct verb tense - Lab reports and research papers should be mainly written in the present tense. You should limit the use of the past tense to (1) describe specific experimental methods and observations, and (2) citing results published in the past.

Tables and Figures - Should be used when they are a more efficient ways to convey information than verbal description. They must be independent units, accompanied by explanatory captions that allow them to be understood by someone who has not read the text.

Writing in the passive voice

"Voice" refers to the way the verb is used in the sentence.  Remember that a sentence has to have a and a , and many verbs require . Here’s an example of :

             verb               direct object

            Purdue Pete      hit                 the baseball.

               action             receives action

In , the subject of the sentence also receives the action.  The doer of the action is someone else.  Here’s an example of :

              verb           

The baseball         is hit         by Purdue Pete.

       action        who did the action

Examples of passive voice in lab reports

200mL of distilled water was poured into a 500 mL beaker.

I poured 200mL of distilled water in a beaker. (active voice)

Pour 200mL water in a beaker. (direction/command)

The covered crucible was mounted on a ring stand.

We put the crucible on a ring stand. (active voice)

Set the crucible on a ring stand. (direction/command)

The temperature was initially measured at 75°C.

I measured the temperature at 75°C. (active voice)

Measure and write down the temperature. (direction/command)

It's understood that all actions were done by the experimenter.

Avoiding Plagiarism

  • Avoiding Plagiarism From Purdue's OWL

Passive voice information derived from original work at Delta College Teaching/Learning Center

http://www.delta.edu/files/TLC/Writing%20Lab%20Reports%2009.doc

Writing a Lab Report

Purdue students explain strategies for dividing the workload for writing a lab report.

Sample Lab Reports

  • Determination of the Alcohol Content of Whiskey [Courtesy of Univ. of Oregon]
  • Synthesis and Characterization of Luminol [Courtesy of Truman State Univ.]
  • Production of Biodiesel [Courtesy of Univ. of Vermont]
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  • Last Edited: Jun 19, 2024 1:55 PM
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How to Write a Lab Report About Titration

Titrations are used to determine an unknown concentration.

How to Calculate & Mix Chemical Solutions

Titrations are standard chemistry laboratory procedures usually used to determine the unknown concentration of a substance. They involve slowly adding a reagent to a reaction mixture until the chemical reaction is complete. The completion of the reaction is usually marked by the color change of an indicator substance. The volume of reagent required to complete the reaction is precisely measured using a burette. Calculations can then be carried out to determine the concentration of the original substance.

Complete your titration ensuring you achieve concordant results. You should have three results within 0.1 cubic centimeters of each other in order to be concordant.

Write your introduction. For a titration, the introduction should include information about what you hope to find out and what substance or product you will be analyzing. Write about the reaction you will be using, including the equation and the conditions required. Include details of the indicator stating the expected color change and writing a brief explanation of the suitability of the chosen indicator.

Describe details of your experimental method in the next section. Include a description of how you made up your solutions, if applicable. State the volume and concentration of any reagents used.

Draw a table to represent the results of your titration. It is customary to write the final burette volume in the first row, the initial burette volume in the second row and the titre in the third row. The titre is calculated by subtracting the initial volume from the final volume. To indicate precision, write all your results in cubic centimeters to two decimal places, adding a zero to the end of the number if necessary. Most standard burettes allow measurement to the nearest 0.05 cubic centimeters. Include all your repeat readings in the table, and indicate which are the concordant results to be used in the calculation of the mean titre. Calculate the mean titre using the concordant results only and record it below your results table.

Calculate your unknown using the mean titre and standard volumetric analysis methods. Lay out your calculations clearly, writing them down in a step-by-step format. This will help you to avoid mistakes, and will also ensure you are given credit for method if you make a minor error. Ensure you add the appropriate units to your answers, and use a suitable degree of precision: usually two decimal places. For guidance on completing the calculations, there are a number of online resources.

Write your conclusion. In a titration, the conclusion is often a simple statement of the experimentally determined parameter. Depending on the aim of the titration, more detail may be required. For example, a brief discussion on whether the results fall within the expected range may be appropriate.

Things You'll Need

Related articles, how to calculate melting & boiling points using molality, acid base titration sources of error improvements, definition of endpoint titration, how to make a 20% sugar solution, how to know when a titration is complete, steps in finding percent yield, the effects of water during a titration experiment, how to calculate the ph titration, how to determine the concentration of a titration, how to make a calibration standard for an hplc, how to calculate the calculations for spectrophotometers, what type of reaction produces a precipitate, how to test for sodium bicarbonate, errors in titration experiments, the advantages of potentiometric titration, titration of sodium carbonate with hydrochloric acid, titration explained, how to identify if a solution is neutral, base or acidic.

  • UCLA Chemistry Department: Some Tips on Writing Lab Reports
  • Germanna Community College: Writing a Formal Lab Report

About the Author

Veronica Mitchell has been a freelancer since 2010, writing mainly in biomedical and health fields, but also covering lifestyle and parenting topics. She has a Master of Arts in veterinary and medical sciences from Cambridge University and is a qualified high-school science teacher.

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40 Useful Lab Report Examples (& Free Templates)

Those who have conducted laboratory tests as students or professionals are usually required to submit a lab report after the process. The purpose of this report is to demonstrate how well you understand the scientific method by conducting, then evaluating an experiment. A lab report format sample is significantly shorter compared to a research paper. Fields that use laboratory reports include technology, science, mathematics, and engineering.

  • 1 Lab Report Examples
  • 2 What is a lab report?
  • 3 Lab Report Formats
  • 4 Why do you need a lab report?
  • 5 Lab Report Samples
  • 6.2 Abstract
  • 6.3 Introduction
  • 6.4 Methods and Materials
  • 6.5 Results
  • 6.6 Discussion
  • 6.7 Conclusion
  • 6.8 Reference
  • 7 Lab Report Templates
  • 8 How to write a lab report?

Lab Report Examples

What is a lab report.

A lab report is a written document that describes and analyzes an experiment performed in a laboratory that involves a scientific concept. These are usually assigned for the following purposes:

  • To conduct scientific research.
  • To formulate a hypothesis or hypotheses about a specific event, behavior, or stimulus.
  • To review relevant or related literature to justify the hypothesis.
  • To allow another person to replicate your experiment by providing enough details and information.
  • To apply statistics for the purpose of testing your hypothesis.
  • To explore various theoretical explanations.
  • To evaluate research methodically and objectively.
  • To communicate precisely and concisely.

When it comes to lab reports, it’s impossible to depend on just one explanation for your results or findings. This means that you should provide as many relevant and potential interpretations as possible. Even when you discover that your findings don’t support your hypothesis, you should still consider those findings valuable.

You can use them to explain that within your study’s contextual constraints, your argument wasn’t reliable. As such, you can move on to other areas of research without making the same mistakes. Also, any findings you have can potentially open other avenues for other people to investigate your hypothesis even under varying conditions.

There are also possibilities that during your experiment, you experience unforeseen conditions or circumstances that weren’t possible to control and isolate. You can use these to justify your final results. Another important aspect that you should consider when writing your report is the grammatical style or voice you use.

In recent years, it’s become acceptable to use the active voice while making references to yourself whenever relevant. When making your report, you should check the instructions of your assignment to make sure you use the right voice. You also have to use a consistent voice throughout your report. If you will use a style guide, follow the guide from start to finish.

Lab Report Formats

Why do you need a lab report.

Laboratory reports are an essential aspect of the scientific process. Here are some reasons why you need this report:

  • You can use it to communicate your findings in the lab to anyone who wasn’t present during the experiments. That way, they can understand and even replicate your experiment.
  • You can use it for future experiments and studies or make suggestions for alterations to methods you have already used.

Make sure to write your laboratory report for those who are already familiar with the scientific study or field but haven’t performed the experiment yet.

Lab Report Samples

What to include in your lab report.

A lab report template usually follows a structured and straightforward procedure. Since each part of the report has its significance, you should spend enough time to write each part carefully. Laboratory reports have specific elements, which you must include:

The title should describe the experiment and show what you analyzed in your experiment.

This is the summary of your experiment and it should familiarize the readers with the research topic. As a rule, you would write the abstract last even though it’s at the beginning of your report. When writing the abstract, try answering these questions:

  • Why did you conduct the experiment or research?
  • What problem will you address?
  • What results did you find?
  • What do the results mean?
  • Do you have a better understanding of the problem now?

Introduction

You will use this part of the report to discuss the problem you’re studying and other theories relevant to understanding your findings. Also, you will state here the hypothesis of your experiment and your motivation for conducting the research.

Methods and Materials

In this section, you will provide your readers with an overview of the apparatus, equipment, or substances you used. You will also list the steps you took throughout the experiment. If you used any specific number of materials, make sure to list these details too. For the steps, you need to list these as you performed them during the experiment.

The results are the data you have found or collected from your experiment. Provide an explanation of how you collected this data. You can use charts , graphs, and other visual aids when presenting the data in this section.

This section is where you will analyze the results of your experiment along with providing a discussion of your data. You need to provide an analysis of the weaknesses and strengths of your experiment’s design, then compare your results with the results of similar experiments. Try to answer these questions while writing this section:

  • What do your findings indicate?
  • What is the significance of the results?
  • Have you found any knowledge gaps?
  • Have you raised any new questions?

This section will serve as the summation of your experiment. You need to clearly state what you learned from the experiment and its significance.

Don’t forget to cite all of the sources that helped support your claims or explain any background information. You should list these references in this section.

Lab Report Templates

How to write a lab report.

People involved in scientific experimentation or investigations should know how to write scientific reports. The main part of scientific investigations takes place in the lab and this may include connecting equipment, obtaining samples and supplies, repairing, checking the consistency of each apparatus, calibration, and data collection. You can do all of these things through experimentation. After conducting the experiment, you would then spend a lot of time presenting the results in an objective, concise, conclusive, and critical format.

This is the laboratory report . An organized report is more influential and effective compared to one without a structure. There aren’t any standard rules for writing a good report. But you should know that you may only get one chance to influence your readers.

A badly-written report will turn your reader off while a well-written one will have an impact on your credibility. It can give you better chances of promotion or employment. Your report can also catch the attention of the scientific community. Here are the steps to follow when writing this report:

  • Think of the Title

Remember that the title of your report will draw the first impression from your readers. As such, you need to have an effective title that will communicate your topic or findings in specific terms. The title doesn’t have to be very thought-provoking or creative. The important thing is to make it informative.

  • Write the introduction

The introduction will provide your readers with significant background information, explain the experiment, and what it will accomplish, and highlight its importance. This section should include a hypothesis and a purpose because you will go back to these in your conclusion when you evaluate your entire experiment.

A well-written introduction must cite all relevant sources like journal articles and more to provide accurate background information. When writing the introduction, you may consider using the funnel method. This involves starting with your topic’s broadest point of interest. From there, gradually narrow down the information to more specific details.

  • List the methods and materials

When it comes to the methods, you should include the details of the steps you used to gather your data, then analyze it. You should provide enough details so that others can evaluate or follow your procedures. When writing this section, use the past tense. If there are situations where you must include a long list of materials or steps, it’s recommended to place them in a separate Appendices section. Just remember to refer to them in the text too.

You should also provide a description of your experimental design, materials, subjects, and procedures you used for collecting and analyzing the data. Then include a list of materials and equipment you used to collect data. Specify the names of the models of any specialized equipment you used. Include a detailed description of your experimental conditions and settings. If needed, add labeled images or diagrams of the exact set-up of the experimental equipment.

Then also add an explanation of how you controlled extraneous variables either through fixing or restricting them at a certain level. When describing your procedures, make sure to write the exact steps you took to collect data – and list these chronologically. You should also provide sufficient information so that anyone who wants to replicate your experiment can do so successfully. Be as concise as possible and add detailed information wherever appropriate.

When conducting an experiment in a lab, there is a high chance that you will follow a laboratory manual while gathering data. If you’re a student, your instructor might allow you to reference the manual, then state whether you modified any steps for practical considerations.

But there are instructors who might ask you to rewrite the procedures in the laboratory manual as complete sentences and coherent paragraphs while taking note of any changes you have made to the steps during your experiment. If you will perform extensive data analysis, make sure to state the analysis you have planned too. This may include the types of tests you will perform and any relevant software or programs you will use for calculations.

  • Indicate the results and the discussion

In this section, you will include all of your results along with any relevant tables and figures with their proper labels. Your results should use the narrative found in the materials and methods section.

You should explain your results through your figures and tables without using too much text. Or if you will explain your results and discussions through words, you don’t have to add too many tables and figures. For example, in chemistry, you would write the results and discussions as a single section. But in biology, you would write them separately

It is in the discussion section where you will use theories to explain how you have achieved your results. Also, explain what those results might imply. Don’t forget to include any mistakes you have committed and how those mistakes may have influenced your data. Remember that discussion isn’t only about reporting results.

You also have to analyze them. This means the inclusion of shapes of graphs, discussion trends, implications of the data, comparisons to known theories or values, and any outliers. Also, a discussion about the accuracy of your results is essential. You should know exactly what your instructor will require for this section.

  • Come up with the conclusion

The final section of your report is the conclusion. This section will contain a summary of your experiment’s findings along with a short overview of the weaknesses and strengths. Also, include any implications your study has for future research. There are some reports that don’t require a conclusion because it will overlap with the discussion. Before you add or omit this section, confirm with your instructor first.

  • Write the abstract

The abstract will provide a comprehensive yet concise summary of your research project. The style you use in writing this should be short, but you don’t have to use note form. You can look through samples if you need guidance. The aim of the abstract is to briefly explain the following:

  • Begin with a 1 to 2 sentence summary that provides the rationale and aim of your study.
  • Describe the setting and participants.
  • Describe the method, design, experimental treatment, questionnaires, surveys, tests, and more.
  • Describe the main findings including any relevant statistics along with significance levels.
  • The final sentences should outline your study’s contribution to the knowledge within the literature.

While you will place the abstract at the start of your report, you would write this part at the end since you will summarize the information from the other sections of your lab report.

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Example of a poorly written lab report with comments highlighted in parenthesis.

Return to Laboratory report Instruction main page Example of a well-written lab report

Lab Report #3 (title uninformative) Carey (not enough information)

Adult male mating behavior suggested that the change in color from fifth instars to adults might enable males to discriminate between nymphs and adults. Mating experiments were performed. The null hypothesis that dorsal color pattern does not affect male mating behavior was tested. (Lacks background information. What organism? Not enough detail about methods and what was measured. No results)

Missing "Introduction" heading

"Ontogenetic color change at the time of sexual maturation is advantageous to fish." (Fricke 1980). This is also true in reptiles. (Little background theory. Use of a direct quote. Information without a citation.) The mating behavior of male Largus californicus suggests that males may be using visual cues, perhaps in addition to pheromonal cues, to distinguish between fifth instars and adults for mating attempts. Fifth instars are shiny blue-black and almost adult sized. Adults (both males and females) are black with orange borders around the thickened portion of the hemelytra and pronotum (Booth, 1990). Although males were never observed to mount nymphs, they do mount other adults, and persist if they have mounted a female and release within a few seconds if they have mounted another male. Their distinctive courtship behavior allows an observer to identify immediately the initiation of a mating event. This consists of the male orienting towards the female when he is approximately 1 cm away, rapidly waving his antennae, leaping onto the female's back, and agitatedly grabbing the female with his legs. As their genitals do not immediately join, it is possible to separate a pair before they actually mate.

These bugs do not fly and are easily handled and painted without significantly disrupting their normal behavior. Mating experiments were performed to prove the hypothesis that males use the color to distinguish between fifth instars and adults. (Not enough detail about experiment. No null hypothesis. Starting out biased by attempting to prove alternate hypothesis.)

Materials and Methods

See lab handout for details. (Do not assume reader has access to handout)

Materials: black paint, clear paint, bugs, boxes

The three treatments will be referred to as normal, clear, and black for brevity.

After each painting, place the female in a clear plastic box. Introduce each male one at a time into the box at the point farthest from the female. Record the time to mount. Do the same for the controls. (Lacking important details, listing of chemicals and apparatus, undefined codes, no sample size, written as instructions, statistical analyses not mentioned.)

See Figures and Tables. Males mounted black painted females in 62.5 sec on average. Males mounted clear painted females in 35.4 sec on average. Males mounted normal females in 43.9 sec on average. (Sentence one does not say anything. Does not give information about each table and figure separately. List of numbers repeated from table. Ignores ANOVA p values and fails to address null hypothesis.)

The null hypothesis was accepted. Other experiments are necessary to determine the nature of the communication between adults and between adults and nymphs.

(Null hypothesis not repeated. Cannot reject the null hypothesis rather than accepting it. What do the results mean? Not compared to other published results. Be more specific about other experiments.)

Fricke, H. W. 1980. Juvenile-adult colour patterns and coexistence in the territorial coral reef fish Pomacanthus imperator. Mar. Ecol. 1 (Needs page numbers. Not in alphabetical order.)

Booth, Carey. Biology of Largus californicus (Hemiptera: Largidae). Southwestern Naturalist 35: 15-22 (1990). (Should use initials only. Date goes after name. Underline species name.)

Zdarek, J. 1970. Mating behaviour in the bug, Pyrrhocoris apterus L. (Heteroptera): ontogeny and its environmental control. Behaviour 37: 253-268. (Not cited in text of report, should not be here.)

Bio 101 lab handout (Incomplete reference. Not cited properly in text either.)

Figure 1. Repeated measures ANOVA

Experiment
Normal
Clear
Black
15
15
15
43.9 ± 10.9
35.4 ± 6.1
64.7 ± 20.5
0
0
1

1.42 2,28 0.26

Control
Trial 1
Trial 2
Trial 3
14
14
14
30.4 ± 7.2
19.0 ± 3.8
19.6 ± 5.4
0
0
0

1.34 2, 26 0.28

(Should be Table 1 as it is not a figure. Insufficient caption. Columns not labeled. Lacks information describing the experiment in footnotes)

Figure 1: Mean male mount time (sec) under three experimental conditions.

(Insufficient legend, treatments not defined, vertical lines not defined)

Figure 1-B:

(Should be Figure 2. Lacks a legend. Axis labels uninformative. Should have same y-axis scale as first figure for ease of comparison)

IMAGES

  1. How to Write a Hypothesis

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  6. FREE 11+ Research Hypothesis Templates in PDF

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VIDEO

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  4. Solved Example#16.11 ||Chapter #16 ||Statistical Inference & Hypothesis Testing ||

  5. Lab Reports (Part 5A): Hypothesis (Criteria)

  6. Solved Example#16.14 ||Chapter #16 ||Statistical Inference & Hypothesis Testing ||

COMMENTS

  1. How to Write a Strong Hypothesis

    Developing a hypothesis (with example) Step 1. Ask a question. Writing a hypothesis begins with a research question that you want to answer. The question should be focused, specific, and researchable within the constraints of your project. Example: Research question.

  2. PDF Biology Lab Report Sample

    Example hypothesis: If the number of serial dilutions increases, the number of bacterial colonies ... Biology Lab Report Sample, Cont'd References ____ Citations are provided for every reference cited in the report and are in APA format. Please consult the Writing Center's "APA Sample Paper" or Purdue Owl

  3. How to Write a Lab Report

    Lab Report Example (Continued) Hypothesis: Now, state your hypothesis. It's important to note that a hypothesis is not the same as predicting a future outcome of an experiment. ... Lab Report Example. Hopefully, these descriptions have helped as you write your next lab report. Remember that different instructors may have different preferences ...

  4. How To Write A Lab Report

    Introduction. Your lab report introduction should set the scene for your experiment. One way to write your introduction is with a funnel (an inverted triangle) structure: Start with the broad, general research topic. Narrow your topic down your specific study focus. End with a clear research question.

  5. How to Write Hypothesis for Lab Report

    A hypothesis is a tentative statement that proposes a possible explanation for some phenomenon or event. A useful hypothesis is a testable statement that may include a prediction. When Are Hypotheses Used? The keyword is testable. That is, you will perform a test of how two variables might be related. This is when you are doing a real experiment.

  6. How to Write a Lab Report: Step-by-Step Guide & Examples

    A typical lab report would include the following sections: title, abstract, introduction, method, results, and discussion. The title page, abstract, references, and appendices are started on separate pages (subsections from the main body of the report are not). Use double-line spacing of text, font size 12, and include page numbers.

  7. How to Write a Strong Hypothesis

    Step 5: Phrase your hypothesis in three ways. To identify the variables, you can write a simple prediction in if … then form. The first part of the sentence states the independent variable and the second part states the dependent variable. If a first-year student starts attending more lectures, then their exam scores will improve.

  8. How to Write a Lab Report

    Graphs and figures must both be labeled with a descriptive title. Label the axes on a graph, being sure to include units of measurement. The independent variable is on the X-axis, and the dependent variable (the one you are measuring) is on the Y-axis. Be sure to refer to figures and graphs in the text of your report: the first figure is Figure ...

  9. How to Write a Good Lab Report

    Report: A sample lab report for this activity is provided as an example for you to follow when writing future lab reports. Sample Lab Report: Experimental Investigation of C/D Abstract. In this investigation, we examined the hypothesis that the circumference (C) and diameter (D) of a circle are directly proportional.

  10. PDF how to write a lab report + sample report

    A. A clear discussion of the results obtained in the lab, including examples from the data. B. Clearly state whether or not the hypothesis is supported by the data. C. Clearly and accurately explain the scientific principles that produced the results (scientifically why the hypothesis was right or wrong). D. Clearly state what was learned in ...

  11. Scientific Reports

    This handout provides a general guide to writing reports about scientific research you've performed. In addition to describing the conventional rules about the format and content of a lab report, we'll also attempt to convey why these rules exist, so you'll get a clearer, more dependable idea of how to approach this writing situation ...

  12. Complete Guide to Writing a Lab Report (With Example)

    As with all forms of writing, it's not the report's length that matters, but the quality of the information conveyed within. This article outlines the important bits that go into writing a lab report (title, abstract, introduction, method, results, discussion, conclusion, reference). At the end is an example report of reducing sugar ...

  13. How to Write a Lab Report

    For example, 12-point Times New Roman. Double-space the report. Include a page number, usually either in the top or bottom right corner of each page. Clearly separate specific sections of the report with headings and subheadings. Below is a quick overview of how to format a basic lab report:

  14. PDF Writing a Formal Lab Report

    Lab reports should be thorough, but repetition should be avoided. The entire report should be clear and straightforward. Write in the third person. Avoid using the words "I" or "we" when referring to the experimental procedure. For example, instead of "I boiled 50 mL of water for 10 minutes," the report should read, "50 mL of ...

  15. Student Tutorial: Introduction to Writing Lab Reports

    An effective introduction to a lab report typically performs the following tasks, generally in the order presented: 1. it establishes the learning context for the lab by: a. saying what the lab is about, that is, what scientific concept (theory, principle, procedure, etc.)Ý the researcher is supposed to be learning about by doing the lab; and. b.

  16. How to Write the Perfect Chemistry Lab Report: A Definitive Guide

    The next section is the Introduction and it begins with this word in the left upper corner of your report. It should consist of no more than a couple of paragraphs and end with at least one hypothesis. The body of your project consists of the procedure, materials and methods employed; data; results and observations.

  17. LabCheck : Improving your lab report

    Improving your Introduction. successfully establishes the scientific concept of the lab. To establish the scientific concept for the lab you need to do two things: 1. state what the lab is about, that is, what scientific concept (theory, principle, procedure, etc.) you are supposed to be learning about by doing the lab.

  18. Example of a well-written lab report

    Example of a well-written lab report. Return to Laboratory report Instruction main page Example of a poorly written lab report ... As the null hypothesis (that males' time to mount is not significantly affected by color of the female) was not rejected, males evidently used those other traits in seeking a mate. The male behavior of mounting ...

  19. PDF APPENDIX V: WRITING A LAB REPORT IMRAD before you begin writing and

    Lab reports, like journal articles, communicate your work to others and help you to organize and analyze your data. Scientific journal articles have a particular form - IMRAD or Introduction, Methods, Results, and Discussion. Read the following information pertaining to writing a lab report both before you begin writing and after you have ...

  20. Writing Your Lab Report/Worksheet

    Write in the third person - Scientific experiments demonstrate facts that do not depend on the observer, therefore, reports should avoid using the first and second person (I,me,my,we,our, OR us.). Using the correct verb tense - Lab reports and research papers should be mainly written in the present tense.You should limit the use of the past tense to (1) describe specific experimental methods ...

  21. How to Write a Lab Report About Titration

    The titre is calculated by subtracting the initial volume from the final volume. To indicate precision, write all your results in cubic centimeters to two decimal places, adding a zero to the end of the number if necessary. Most standard burettes allow measurement to the nearest 0.05 cubic centimeters. Include all your repeat readings in the ...

  22. 40 Useful Lab Report Examples (& Free Templates)

    What is a lab report? A lab report is a written document that describes and analyzes an experiment performed in a laboratory that involves a scientific concept. These are usually assigned for the following purposes: To conduct scientific research. To formulate a hypothesis or hypotheses about a specific event, behavior, or stimulus.

  23. Example of a poorly written lab report with comments in red

    Example of a well-written lab report. Lab Report #3 (title uninformative) Carey (not enough information) Abstract. Adult male mating behavior suggested that the change in color from fifth instars to adults might enable males to discriminate between nymphs and adults. Mating experiments were performed.