creative writing

how to write an effective lab report

INDIANA UNIVERSITY BLOOMINGTON IU BLOOMINGTON IU BLOOMINGTON

How To Find Articles with Databases
How To Evaluate Articles
How To Read A Scientific Paper
How To Interpret Data
How To Write A Lab Report
How To Write A Scientific Paper
Get More Help
Reference: Encyclopedia, Handbooks & Dictionaries
Research Tools: Databases, Protocols & Citation Locators
E-Journal Lists by Subject
Scholarly vs Popular
Search Tips
Open Resources
E-Journal lists by subject
Develop a Research Question

STEM disciplines are important and growing areas of learning. Being able to read, write, and understand information in science, technology, engineering, and mathematics is crucial to academic success. Learning these skills will help you to not only become a working professional in your field, but develop and grow in all areas of study!

E-journals List | DOI Search

[email protected] ACM : Computer Science arXiv : Physics BioOne Browzine : includes a mobile app; this is a journal reading site that includes many of IU's high caliber licenses Cold Spring Harbor Protocols Dissertations and Theses Foundation Directory Online GeoRef | GeoScience World Global Electronic Theses and Dissertations (open access) IEEE : Engineering JSTOR : Historical content, and more Journal Citation Reports : Impact Factors JoVE: Journal of Visualized Experiments MathSciNet PsycInfo PubMed Reaxys SciFinder : First-time users must register with their @iu.edu email address. SciFinder-n Scopus Springer Nature Experiments/Protocols Web of Science

Science Librarians: Emily Alford : public health: applied health sciences, health & wellness design, & government information, [email protected] Jian Liu : biological sciences, earth and atmospheric sciences, [email protected] Amy Minix : cognitive sciences, neurosciences, nursing, optometry, psychology, speech and hearing sciences, [email protected] Bob Noe l: astronomical, computer, engineering, informatics, library, mathematical, physical, statistical sciences, [email protected] Jennifer Simms : biological, chemical, health sciences, [email protected]

Next: How To Find Articles with Databases >>
Last Updated: Feb 21, 2023 10:29 AM
URL: https://guides.libraries.indiana.edu/STEM

Indiana University Libraries homepage

View all Library Hours

Create account

How to write the perfect lab report

May 11, 2020 • Jessica Hess • Science • Tips & Tricks • Writing

What is a lab report?

The main purpose of a lab report is to summarize scientific research you've performed and explain how the results relate to your hypothesis. Technical reports like these are an important part of science because, as a scientist, you have a responsibility to communicate your findings, what you learned, and why it matters.

Your report should demonstrate that you understand:

GOOD lab reports

To write the perfect lab report, you need to think about who you're writing for and what they want to know. I recommend writing as if your reader has the same level of experience as you, i.e., a student taking the same course but in a different lab section. The look of your lab report may vary based on your research topic, but you should always aim to:

BAD lab reports

In my experience, bad lab reports are often written last minute and lack a general understanding of the experiment. I recommend starting on your report early enough to ask a friend or two to review it for you. If your friends don't understand what your report is about, it's safe to assume the person grading your report won't either.

The best lab reports have clear, coherent story lines and a natural flow. It should be easy for your reader to understand the purpose of your experiment, findings, and the significance of your work.

Grammar is another area where I've seen students struggle. You want to be sure that you're using terminology that flows with your style of writing and that you are confident using on paper AND in a conversation. The way I expand my scientific vocabulary is simple — I stop every time I encounter a word I don't know and Google, YouTube, and PubMed search it until I understand.

[ If you're looking for additional writing help, leave your questions in the comments below so I can answer them in an upcoming post! ]

The structure of a lab report

Writing a lab report can be intimidating, but whether you're a student or Nobel Prize winner, the secret to a great piece of scientific writing is its organization .

I like to think of the report and each of its sections as an extension of the scientific method:

As a whole, a lab report communicates scientific results . The introduction includes background research & states the hypothesis . Materials & methods show how the hypothesis was tested . The results section provides the data . And lastly, the discussion gives a detailed analysis of the data , states if the results support the hypothesis, and sometimes leaves the reader with a new question to investigate !

In general, lab reports require these sections:

The title should be brief and describe the main point of the experiment. Even better if you can come up with a catchy one — scientists love a good pun!

If your instructor asks for a title page , this is usually a cover page that states: the title of your report, your name/lab partners, instructor's name, class section, and date.

The abstract should be a brief (one paragraph) overview of what is in the report. It should summarize the purpose of the experiment, your hypothesis, methods, key findings, significance, and conclusions. The goal is to get your reader interested in the work enough to keep reading!

This section can be challenging to write, and is best saved for last.

Introduction

The introduction should state: the purpose of the experiment, relevant background/previous research on the subject, the hypothesis, and the reasons you believe the hypothesis is feasible. Include in-text citations as appropriate.

Details about the experiment should be written in past tense, since it has already been finished. Theory, however, should be written in present tense. Always write this part in your own words, rather than quoting or paraphrasing references.

This section should set the scene for what's to follow.

Materials & Methods

In the materials and methods , you want to describe the procedures used to test your hypothesis in detail. Describe what you did, in the order you did it. Never use bullet points or numbered steps! You should be detailed enough that someone could reproduce your experiment and obtain similar results using what you've written.

In the past, scientists avoided writing in the first person (I or we) because who performed the experiment is usually not important to the procedure. However many style guides now recommend using the active voice, so you'll want to check in with your instructor. You can write that you recorded results, or how you recorded them, but you shouldn't write about what your results were just yet. Remember that you're describing what already happened, so you should again write in the past tense.

This section is merely detailing how you tested your hypothesis.

The results section is where you present the data you collected in the experiment and describe trends you observed. You can write this part in the past tense because the experiment has already happened.

Results is usually a short section because at this point you're just reporting facts, not interpreting your data or drawing conclusions just yet!

Data should be organized into tables, figures, and diagrams. Use as many visual aids as you need to clearly show how your hypothesis was or wasn't supported. Each should be appropriately labeled and clearly state what is being shown.

Remember to keep it professional — never use images you found on the web or have taken with your cell phone unless you've been asked to do so by your instructor.

This section should include all of your tables/figures and explicitly state all significant results in verbal form.

The discussion section is where you explain, analyze, and interpret your findings in detail .

This section focuses on the significance of your results, weaknesses in the experiment, and what you have learned.

The references section consists of an alphabetical or numerical list of the resources you used in writing your report. All full citations on your References list should match to an in-text citation.

Include your lab manual and any external research you have done. Formatting can vary based on the field of research and personal preference, so ask your instructor what is expected of you. All references and in-text citations should be formatted consistently throughout the report.

This section should be constructed as in-text citations are added to your report.

...and that's it, your perfect lab report is done!

← Older Post Newer Post →

Hi! Just to say thank you for this post. Currently having a hard time while writing my lab report since I take so long time for a break. Now, after getting back to study, I found myself a lil bit hard to finish my assignment on my own but I really don’t want to depend on others, and here I am, read everything I can on google to make me feel a lil bit easier. Thank you once again for writing this post.

Leave a comment

Please note, comments must be approved before they are published

choosing a selection results in a full page refresh

How to Write a Lab Report

Lab reports describe your experiment.

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 a format for 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 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 that anyone could read this section and duplicate your experiment. Write it as if you were giving direction 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, 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.

how to write an effective lab report

By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.

Have a language expert improve your writing

Run a free plagiarism check in 10 minutes, generate accurate citations for free.

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

Published on May 20, 2021 by Pritha Bhandari . Revised on July 15, 2022.

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.

Table of contents

Structuring a lab report, introduction, 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.

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.

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.

Receive feedback on language, structure, and formatting

Professional editors proofread and edit your paper by focusing on:

how to write an effective lab report

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:

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:

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.”

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

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:

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:

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

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.

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.

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:

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.

Cite this Scribbr article

If you want to cite this source, you can copy and paste the citation or click the “Cite this Scribbr article” button to automatically add the citation to our free Citation Generator.

Bhandari, P. (2022, July 15). How To Write A Lab Report | Step-by-Step Guide & Examples. Scribbr. Retrieved March 6, 2023, from https://www.scribbr.com/academic-writing/lab-report/

Is this article helpful?

Pritha Bhandari

Pritha Bhandari

Other students also liked, guide to experimental design | overview, steps, & examples, how to write an apa methods section, how to write an apa results section, what is your plagiarism score.

Princeton Correspondents on Undergraduate Research

How to Write An Effective Lab Report

how to write an effective lab report

Whether you are in lab for general chemistry, independent work, or senior thesis, almost all lab experiments will be followed up with a lab report or paper. Although it should be relatively easy to write about an experiment you completed, this is often the most difficult part of lab work, especially when the results are unexpected. In this post, I will outline the components of a lab report while offering tips on how to write one.

Understand Your Experiments Thoroughly

Before you begin writing your draft, it is important that you understand your experiment, as this will help you decide what to include in your paper. When I wrote my first organic chemistry lab report, I rushed to begin answering the discussion questions only to realize halfway through that I had a major conceptual error. Because of this, I had to revise most of what I had written so far, which cost me a lot of time. Know what the purpose of the lab is, formulate the hypothesis, and begin to think about the results you are expecting. At this point, it is helpful to check in with your Lab TA, mentor, or principal investigator (PI) to ensure that you thoroughly understand your project.

The abstract of your lab report will generally consist of a short summary of your entire report, typically in the same order as your report. Although this is the first section of your lab report, this should be the last section you write. Rather than trying to follow your entire report based on your abstract, it is easier if you write your report first before trying to summarize it.

Introduction and Background

The introduction and background of your report should establish the purpose of your experiment (what principles you are examining), your hypothesis (what you expect to see and why), and relevant findings from others in the field. You have likely done extensive reading about the project from textbooks, lecture notes, or scholarly articles. But as you write, only include background information that is relevant to your specific experiments. For instance, over the summer when I was still learning about metabolic engineering and its role in yeast cells, I read several articles detailing this process. However, a lot of this information was a very broad introduction to the field and not directly related to my project, so I decided not to include most of it.

This section of the lab report should not contain a step-by-step procedure of your experiments, but rather enough details should be included so that someone else can understand and replicate what you did. From this section, the reader should understand how you tested your hypothesis and why you chose that method. Explain the different parts of your project, the variables being tested, and controls in your experiments. This section will validate the data presented by confirming that variables are being tested in a proper way.

You cannot change the data you collect from your experiments; thus the results section will be written for you. Your job is to present these results in appropriate tables and charts. Depending on the length of your project, you may have months of data from experiments or just a three-hour lab period worth of results. For example, for in-class lab reports, there is usually only one major experiment, so I include most of the data I collect in my lab report. But for longer projects such as summer internships, there are various preliminary experiments throughout, so I select the data to include. Although you cannot change the data, you must choose what is relevant to include in your report. Determine what is included in your report based on the goals and purpose of your project.

Discussion and Conclusion

In this section, you should analyze your results and relate your data back to your hypothesis. You should mention whether the results you obtained matched what was expected and the conclusions that can be drawn from this. For this section, you should talk about your data and conclusions with your lab mentors or TAs before you begin writing. As I mentioned above, by consulting with your mentors, you will avoid making large conceptual error that may take a long time to address.

There is no correct order for how to write a report, but it is generally easier to write some sections before others. For instance, because your results cannot be changed, it is easier to write the results section first. Likewise, because you also cannot change the methods you used in your experiment, it is helpful to write this section after writing your results. Although there are multiple ways to write and format a lab report or research paper, the goals of every report are the same: to describe what you did, your results, and why they are significant. As you write, keep your audience and these goals in mind.

— Saira Reyes, Engineering Correspondent

Share this:

Share on Tumblr

how to write an effective lab report

Written by Wun Chiou

(A Former UCLA First-Year Lab Courses Teaching Assistant)

A lab report is more than just something you turn in to (hopefully) get a good grade. It's your opportunity to show that you understand what is going on in the experiment, which is really the most important part of doing it. In addition, I think it's actually very good practice for getting across your thoughts about the science you are doing in a manner that the reader can understand.

What you write in your laboratory notebook is an actual account of what you have done in a given experiment, like a very detailed diary. You should be able to come back to it at some point, read what you wrote before, and reproduce what you did before. So should anyone else reading your notebook, for that matter. That way, if you make some amazing discovery, like blue aspirin is better than white aspirin (btw: don't eat anything in, from, or created in lab to see if this is right), you will have a permanent record of it to remind you of your greatness. There are three basic parts to a lab report: pre-lab , in-lab , and post-lab . In this document, I've written some helpful tips that might help you through your lab-report woes. I won't include everything you have to do (you should look on VOH for the report guidelines), but just a few key ideas.

I. Introduction

The introduction discusses the problem being studied and the relevant theory. Ideally, it would take up about 4-5 sentences. The main idea here is to give the reader an idea of what you are going to do in a short paragraph. There are different styles to do this. You should try to write it in your own words, rather than paraphrasing or quoting the lab manual (but if you have to, be sure to include the appropriate references). It's always a good idea to read the entire experiment in the manual before you begin your introduction. I suggest the following:

Background sentences: state why you want to do the experiment, why is it relevant, what other kinds of similar experiments have been done in the past.

Goal: In one sentence, state what you are going to do in the experiment and what you hope to find. This is probably the most important part of the introduction. You should also list explicitly any main chemicals with which you are dealing (vinegar, aspirin, NaOH) and any techniques you will be utilizing (titration, recrystallization, spectrophotometry, etc.). For example, "In this experiment, we will determine the buffer capacity of a weak acid buffer of acetic acid / acetate ion by titration with both a strong acid, HCl, and a strong base, NaOH."

Other procedures or theory: If you need to elaborate on some of the techniques you stated in your goal (or couldn't state in your goal), you can write a couple more sentences about them afterwards. Or you can add anything else that you might think is relevant, like additional major procedural steps you will take.

Keep it sho rt!

II. Procedural Flowchart

This part of the pre-lab should take no more than one page. A good flowchart should give a reader an immediate idea of what's need to be done in the laboratory except in a less detailed format. Think of a flowchart as a "road map" of the experiment. It gives a reader a "pictorial" representation of the experimental procedure. In general there are two major steps when constructing the flowchart. First, read the experimental procedure carefully. Second, rewrite the procedures in a flowchart format. Keep in mind that the flowchart should be brief and cover all the steps in a simple and easy to follow manner. There should be no complicated sentences or paragraphs in the flowchart. You will have to do a lot of rewriting in order to simplify the procedures into a flowchart format. This is exactly why we want you to do it. This gives you a chance to THINK about what you read and how to rewrite it in a way that can be implemented into a flowchart.

Always remember to reference where the experimental procedures are coming from in the pre-lab report.

Please DO NOT simply copy the entire procedure (or majority of the procedure) and make it looks like a flowchart.

IN-LAB RESPONSIBILITY

Always write in pen. You can't really erase anything, anyway, because of the carbon paper below it. White-out is a big no-no, too. Always record data directly into your lab notebook. I know some people like to be neat, and have nice formatting and all that, but it's more important to make sure you record all of the data immediately in case you forget what you wanted to say later or you forget to copy other data into your notebook. Never scratch something out completely. Yeah, nobody's perfect and of course also nobody wants to be reminded of that, but you may discover that you were right in the first place, and now you wish you could read what you wrote before. Also, if you make a mistake it's a good idea to keep a record if it so you (or someone else trying to do your experiment) can remember to not make the same mistake twice.

II. Observations

In addition to writing down all those numbers (data), you should keep an eye (nose, ear, etc.) on what is actually happening in the experiment. If you add one thing to another and it evolves a gas, gets hot or cold, changes color or odor, precipitates a solid, reacts really quickly or slowly, or anything noticeable, you should write down that observation in your lab notebook. Other things to consider including are: make and type of any machine you are using, concentrations of all the standards you used, and etc. One of the reasons you are doing this goes back to what I said about mistakes earlier. An experiment is exactly that: an experiment. If it turns out that you get an unexpected result, you can go back and trace your observations to see where the error occurred. If you don't have any observat ions, this is really hard to do. The bottom line: write what you do and do what you write.

POST-LAB REPORT

Recopy your data from the in-lab here in a nice neat format (tables are usually nice and neat). This is your chance to organize it into a more readable form now that you are done with the experiment and impress the TA with your organizational skills.

II. Calculations

It's a good idea to write out all the formulas you use in your calculations. Personally, I like to work through the problem using just the formula, and then plug in the numbers at the end to get my final answer. Also, show all of your work. One more point is to be sure to include the units when you are doing a calculation, and don't drop the units halfway through the calculation. This is actually a pretty powerful tool because if your answer has the wrong units you know you must have made an error somewhere along the way. Conversely, if your answer has the correct units, you could still be wrong, but at least you are on the right track (and probably much of the time your answer is correct, too!) You can even do the calculation using just units and no numbers and see if the units cancel out in the right way to test if you method is good (this is called dimensional analysis).

III. Conclusion

The conclusion is alot like the introduction except, instead of a summary of what you are going to do, it's a summary of what you did. The reason you have a conclusion is because your lab report might be long and the reader may not remember all the important points that you stated. Also, it gives you a chance to explain anything that might have gone wrong or could be improved, as well as propose future experiments. Like the introduction, it should be short and to the point. Again, these are only my suggestions, but here's what I think you should always include:

What you did: Reiterate your procedures briefly (including any changes you made).

What you found: Restate any results that you may have calculated (with errors if applicable). You don't need to include the raw data, but if you calculated an average over several trials, state the average (not each trial). Usually you want to report the results as x +/- y (like 2.345 +/- 0.003), where y is the absolute error in x. Another option, if you calculated the relative error, is x +/- z% (like 2.345 +/- 0.5%), where z is the relative error.

What you think: What do your results mean? Are they good? Bad? Why or why not? Basically, comment on the results. If your experimental error (RAD, RSD) is small or large compared to the inherent error (the error in the standards and equipment used), comment on what this means, too.

Errors: Speculate on possible sources of error.

The Lab Report

This document describes a general format for lab reports that you can adapt as needed. Lab reports are the most frequent kind of document written in engineering and can count for as much as 25% of a course yet little time or attention is devoted to how to write them well. Worse yet, each professor wants something a little different. Regardless of variations, however, the goal of lab reports remains the same: document your findings and communicate their significance. With that in mind, we can describe the report’s format and basic components. Knowing the pieces and purpose, you can adapt to the particular needs of a course or professor.

A good lab report does more than present data; it demonstrates the writer’s comprehension of the concepts behind the data. Merely recording the expected and observed results is not sufficient; you should also identify how and why differences occurred, explain how they affected your experiment, and show your understanding of the principles the experiment was designed to examine. Bear in mind that a format, however helpful, cannot replace clear thinking and organized writing. You still need to organize your ideas carefully and express them coherently.

Typical Components

1. The Title Page needs to contain the name of the experiment, the names of lab partners, and the date. Titles should be straightforward, informative, and less than ten words (i.e. Not “Lab #4” but “Lab #4: Sample Analysis using the Debye-Sherrer Method”). 2. The Abstract summarizes four essential aspects of the report: the purpose of the experiment (sometimes expressed as the purpose of the report), key findings, significance and major conclusions. The abstract often also includes a brief reference to theory or methodology. The information should clearly enable readers to decide whether they need to read your whole report. The abstract should be one paragraph of 100-200 words (the sample below is 191 words).

Quick Abstract Reference

May Include:

Restrictions:

ONE page 200 words MAX.

Sample Abstract

This experiment examined the effect of line orientation and arrowhead angle on a subject’s ability to perceive line length, thereby testing the Müller-Lyer illusion. The Müller-Lyer illusion is the classic visual illustration of the effect of the surrounding on the perceived length of a line. The test was to determine the point of subjective equality by having subjects adjust line segments to equal the length of a standard line. Twenty-three subjects were tested in a repeated measures design with four different arrowhead angles and four line orientations. Each condition was tested in six randomized trials. The lines to be adjusted were tipped with outward pointing arrows of varying degrees of pointedness, whereas the standard lines had inward pointing arrows of the same degree. Results showed that line lengths were overestimated in all cases. The size of error increased with decreasing arrowhead angles. For line orientation, overestimation was greatest when the lines were horizontal. This last is contrary to our expectations. Further, the two factors functioned independently in their effects on subjects’ point of subjective equality. These results have important implications for human factors design applications such as graphical display interfaces.

3. The introduction is more narrowly focussed than the abstract. It states the objective of the experiment and provides the reader with background to the experiment. State the topic of your report clearly and concisely, in one or two sentences:

Quick Intro Reference

May include:

Example: The purpose of this experiment was to identify the specific element in a metal powder sample by determining its crystal structure and atomic radius. These were determined using the Debye-Sherrer (powder camera) method of X-ray diffraction.

A good introduction also provides whatever background theory, previous research, or formulas the reader needs to know. Usually, an instructor does not want you to repeat the lab manual, but to show your own comprehension of the problem. For example, the introduction that followed the example above might describe the Debye-Sherrer method, and explain that from the diffraction angles the crystal structure can be found by applying Bragg’s law. If the amount of introductory material seems to be a lot, consider adding subheadings such as: Theoretical Principles or Background.

Note on Verb Tense

Introductions often create difficulties for students who struggle with keeping verb tenses straight. These two points should help you navigate the introduction:

“The objective of the experiment was…”

“The purpose of this report is…” “Bragg’s Law for diffraction is …” “The scanning electron microscope produces micrographs …”

4. Methods and Materials (or Equipment) can usually be a simple list, but make sure it is accurate and complete. In some cases, you can simply direct the reader to a lab manual or standard procedure: “Equipment was set up as in CHE 276 manual.” 5. Experimental Procedure describes the process in chronological order. Using clear paragraph structure, explain all steps in the order they actually happened, not as they were supposed to happen. If your professor says you can simply state that you followed the procedure in the manual, be sure you still document occasions when you did not follow that exactly (e.g. “At step 4 we performed four repetitions instead of three, and ignored the data from the second repetition”). If you’ve done it right, another researcher should be able to duplicate your experiment. 6. Results are usually dominated by calculations, tables and figures; however, you still need to state all significant results explicitly in verbal form, for example:

Quick Results Reference

Using the calculated lattice parameter gives, then, R = 0.1244nm.

Graphics need to be clear, easily read, and well labeled (e.g. Figure 1: Input Frequency and Capacitor Value). An important strategy for making your results effective is to draw the reader’s attention to them with a sentence or two, so the reader has a focus when reading the graph.

In most cases, providing a sample calculation is sufficient in the report. Leave the remainder in an appendix. Likewise, your raw data can be placed in an appendix. Refer to appendices as necessary, pointing out trends and identifying special features. 7. Discussion is the most important part of your report, because here, you show that you understand the experiment beyond the simple level of completing it. Explain. Analyse. Interpret. Some people like to think of this as the “subjective” part of the report. By that, they mean this is what is not readily observable. This part of the lab focuses on a question of understanding “What is the significance or meaning of the results?” To answer this question, use both aspects of discussion:

More particularly, focus your discussion with strategies like these:

Compare expected results with those obtained.

If there were differences, how can you account for them? Saying “human error” implies you’re incompetent. Be specific; for example, the instruments could not measure precisely, the sample was not pure or was contaminated, or calculated values did not take account of friction.

Analyze experimental error.

Was it avoidable? Was it a result of equipment? If an experiment was within the tolerances, you can still account for the difference from the ideal. If the flaws result from the experimental design explain how the design might be improved.

Explain your results in terms of theoretical issues.

Often undergraduate labs are intended to illustrate important physical laws, such as Kirchhoff’s voltage law, or the Müller-Lyer illusion. Usually you will have discussed these in the introduction. In this section move from the results to the theory. How well has the theory been illustrated?

Relate results to your experimental objective(s).

If you set out to identify an unknown metal by finding its lattice parameter and its atomic structure, you’d better know the metal and its attributes.

Compare your results to similar investigations.

In some cases, it is legitimate to compare outcomes with classmates, not to change your answer, but to look for any anomalies between the groups and discuss those.

Analyze the strengths and limitations of your experimental design.

This is particularly useful if you designed the thing you’re testing (e.g. a circuit). 8. Conclusion can be very short in most undergraduate laboratories. Simply state what you know now for sure, as a result of the lab:

Quick Conclusion Reference

Example: The Debye-Sherrer method identified the sample material as nickel due to the measured crystal structure (fcc) and atomic radius (approximately 0.124nm).

Notice that, after the material is identified in the example above, the writer provides a justification. We know it is nickel because of its structure and size. This makes a sound and sufficient conclusion. Generally, this is enough; however, the conclusion might also be a place to discuss weaknesses of experimental design, what future work needs to be done to extend your conclusions, or what the implications of your conclusion are. 9. References include your lab manual and any outside reading you have done. Check this site’s documentation page to help you organize references in a way appropriate to your field. 10. Appendices typically include such elements as raw data, calculations, graphs pictures or tables that have not been included in the report itself. Each kind of item should be contained in a separate appendix. Make sure you refer to each appendix at least once in your report. For example, the results section might begin by noting: “Micrographs printed from the Scanning Electron Microscope are contained in Appendix A.”

To learn more about writing science papers, visit our handout on writing in the sciences .

Writing Studio

Severe Weather – Move Appointments to Online, Friday March 3

Writing a Lab Report: Introduction and Discussion Section Guide

In an effort to make our handouts more accessible, we have begun converting our PDF handouts to web pages. Download this page as a PDF: Writing a Lab Report Return to Writing Studio Handouts

Part 1 (of 2): Introducing a Lab Report

The introduction of a lab report states the objective of the experiment and provides the reader with background information. State the topic of your report clearly and concisely (in one or two sentences). Provide background theory, previous research, or formulas the reader should know. Usually, an instructor does not want you to repeat whatever the lab manual says, but to show your understanding of the problem.

Questions an Effective Lab Report Introduction Should Answer

What is the problem.

Describe the problem investigated. Summarize relevant research to provide context, key terms, and concepts so that your reader can understand the experiment.

Why is it important?

Review relevant research to provide a rationale for the investigation. What conflict, unanswered question, untested population, or untried method in existing research does your experiment address? How will you challenge or extend the findings of other researchers?

What solution (or step toward a solution) do you propose?

Briefly describe your experiment : hypothesis , research question , general experimental design or method , and a justification of your method (if alternatives exist).

Tips on Composing Your Lab Report’s Introduction

Part 2 (of 2): Writing the “Discussion” Section of a Lab Report

The discussion is the most important part of your lab report, because here you show that you have not merely completed the experiment, but that you also understand its wider implications. The discussion section is reserved for putting experimental results in the context of the larger theory. Ask yourself: “What is the significance or meaning of the results?”

Elements of an Effective Discussion Section

What do the results indicate clearly? Based on your results, explain what you know with certainty and draw conclusions.

Interpretation

What is the significance of your results? What ambiguities exist? What are logical explanations for problems in the data? What questions might you raise about the methods used or the validity of the experiment? What can be logically deduced from your analysis?

Tips on the Discussion Section

1. explain your results in terms of theoretical issues..

How well has the theory been illustrated? What are the theoretical implications and practical applications of your results?

For each major result:

2. Relate results to your experimental objective(s).

If you set out to identify an unknown metal by finding its lattice parameter and its atomic structure, be sure that you have identified the metal and its attributes.

3. Compare expected results with those obtained.

If there were differences, how can you account for them? Were the instruments able to measure precisely? Was the sample contaminated? Did calculated values take account of friction?

4. Analyze experimental error along with the strengths and limitations of the experiment’s design.

Were any errors avoidable? Were they the result of equipment? If the flaws resulted from the experiment design, explain how the design might be improved. Consider, as well, the precision of the instruments that were used.

5. Compare your results to similar investigations.

In some cases, it is legitimate to compare outcomes with classmates, not in order to change your answer, but in order to look for and to account for or analyze any anomalies between the groups. Also, consider comparing your results to published scientific literature on the topic.

The “Introducing a Lab Report” guide was adapted from the University of Toronto Engineering Communications Centre and University of Wisconsin-Madison Writing Center.

The “Writing the Discussion Section of a Lab Report” resource was adapted from the University of Toronto Engineering Communications Centre and University of Wisconsin-Madison Writing Center.

Last revised: 07/2008 | Adapted for web delivery: 02/2021

In order to access certain content on this page, you may need to download Adobe Acrobat Reader or an equivalent PDF viewer software.

Physical Measurements-phys 201, dr.erkal

General outline of a laboratory report.

Scientific writing is just as important as scientific investigation or experimenting. Although the major part of scientific investigation takes place in the laboratory--connecting equipment together, repairing, obtaining supplies and samples, checking each apparatus for consistency, calibration, and finally data collection by running the experiment—a great deal of time is spent to present the results in a concise, objective, critical and conclusive format called laboratory report (similar to research paper). Therefore, a well-organized laboratory report is much more effective and influential than one without a structure. There is no short list of instructions for writing a good laboratory report. You may have only one chance to influence your reader. While ineffective writing can turn off the readers, a well-written laboratory report can have impacts on your reputation, chance of employment or promotion. You may also draw the attention of the scientific community to your work and retain them as your readers.

Sections of a laboratory report :

A laboratory report usually have several sections identified by titles. A typical report would include such sections as TITLE, INTRODUCTION, PROCEDURE, RESULTS, and DISCUSSION/CONCLUSION. If you are using a computer to type your work, section headings should be in boldface.

The title can usually draw attention of the reader to your work. It should clearly represent the work presented. If the purpose of the experiment is to measure the gravitational acceleration of the earth using pendulum as the experimental apparatus, the title should be like “ Measurement of the Gravitational Acceleration Using Simple Pendulum ”. Avoid “The” as the first word in the title for it will lead to misleading searches when one uses the database.

State the purpose of the experiment in general terms. For example, “ It is possible to measure the gravitational acceleration using the oscillations of a simple pendulum.”

Review the existing information or the theory . Reader will look for some reminder of the basic information relating to this particular area. This can be done by giving him/her a brief summary of the existing state of knowledge. We can also include a summary of earlier work with proper references.

Supply a paragraph or two about how the basic information , such as an equation representing the behavior of a model (theory), can be used to make measurements.

Indicate what parameter or properties of the system you are measuring. Usually you change a parameter of the system (such as changing the temperature, independent variable ), and measure its effect (such as the length of a metal rod, dependent variable ).

Specify such measurement details as the type of standard or instrument used to make the measurement (for example, meter stick or vernier caliper, etc.). Give the instrument uncertainties. For example, if we are using a meter stick, we can say, “ the length of the rod is measured using a laboratory meter stick accurate to within 1 cm. You may also give, if necessary, an apparatus diagram.

Discussions/Conclusions:

Although these do not make an exhaustive list of do’s or don'ts, they nevertheless offer a framework around which one can write an effective report. In our experiment, some of the items indicated under each section may not be needed. I will give you more feedback in class. I expect that, the lab reports, either typed or handwritten, should be neat, clear, and organized. Points will be deducted for these, as well as for missing units and failing to follow the outline (i.e. title, introduction, procedure, results, conclusion) given above.

IMAGES

Lab Report Writing Service Uk ‒ Get Professional Help With Any Type of Lab Report Writing
Lab Report Guidelines
40 Lab Report Templates & Format Examples ᐅ TemplateLab
format lab report
48+ SAMPLE Lab Reports in PDF
Someone Write My Lab Report. Writer My Lab Report Right Now with a 15% Discount

VIDEO

Lab Report Writting
LAB REPORT PRESENTATION 📓
You and Your Lab Ghost
Common Mistakes Lab Report (Discussion & Conclusion)
How to Write a Formal Lab Report (Empirical Formula Edition)
Report Lab One

COMMENTS

How To Write A Lab Report
Writing Lab Reports · Why was the research done or experiment conducted? · What problem is being addressed? · What results were found? · What are
How to write the perfect lab report
GOOD lab reports · Communicate the findings from your work and help your reader understand them. · Write your procedures with enough detail that
How to Write a Lab Report
Describe the steps you completed during your investigation. This is your procedure. Be sufficiently detailed that anyone could read this section
How To Write A Lab Report
Structuring a lab report · Title: expresses the topic of your study · Abstract: summarizes your research aims, methods, results, and conclusions
How to Write An Effective Lab Report
The introduction and background of your report should establish the purpose of your experiment (what principles you are examining), your
Tips on Writing Lab Reports
First, read the experimental procedure carefully. Second, rewrite the procedures in a flowchart format. Keep in mind that the flowchart should be brief and
The Lab Report
Compare expected results with those obtained. · Analyze experimental error. · Explain your results in terms of theoretical issues. · Relate results to your
Writing a Lab Report: Introduction and Discussion Section Guide
State the topic of your report clearly and concisely (in one or two sentences). Provide background theory, previous research, or formulas the reader should know
How to Write a Lab Report
Sherri Seligson walks you through the steps of writing a lab report for your science
GENERAL OUTLINE OF A LABORATORY REPORT
A laboratory report usually have several sections identified by titles. A typical report would include such sections as TITLE, INTRODUCTION, PROCEDURE, RESULTS