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Chemical History of the Candle

Lab Assignment 1: The Lab Report

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The Lab Report

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How to write a Lab Report

The lab equipment lists a lab notebook. Please be sure that you have a dedicated, spiral-bound notebook for your lab work, preferably with graph paper pages. It should be large enough for you to entery drawings and create tables.

First, prepare your lab notebook and do some planning about how you will use it.

  1. Create a table of contents area at least 4 pages long. Label these pages in the corner "ToC1", "ToC2", etc.
  2. Number the remaining pages of your notebook now. Never remove or add pages to your lab notebook, although you can tape or glue in photos or data reports from instruments if you need to.
  3. Start labs on the right side of the page if you are right-handed, or on the left side of the page if you are left-handed. Do not write on the facing page during your experiment unless absolutely necessary. It is usually easier to write without the spiral in the way during the experiment run, when you may have little room or time!
  4. After your experimental run is concluded, use the facing pages to add notes, comments, sample calculations, drawings, and photos.

Next, determine what curious object you will observe: we will investigate how a candle burns.

Get a sense of the scope of your observations: we will experiment with several different areas of burning candle characteristics, not just focus on one area. Make a note of your goals in your lab notebook.

When you investigate a curious object, you start with close observation. Before you take any measurements, you must first try to identify what things are present, both as part of the object and part of its surroundings. Try not to think about what you should observe because you already know something about the situation, but look closely at what you do observe. Sometimes we are so conditioned by our expectations that we may easily miss important details that call our theories into question!

As you look at your curious object, make a mental list of the characteristics you could or should note and identify those that are subject to measurement or quantification. Check for shape and color, brightness and intensity of light, heat and temperature, size and mass (amount of matter) — and the boundaries where these change. Look for similarities or differences and patterns in composition, behavior, circumstances or environmental conditions surrounding the curious object. Make notes of these observations in your lab book.

Watch the curious object over time, and note not only what changes occur, but the rate of change. Look for characteristics most likely to affect the rate of change (amount of matter, temperature, outside forces acting on the object).

Now you are ready to make an hypothesis, an educated (by your observational experience) prediction of how the curious object will behave in a given set of circumstances. The best way to test this is to identify a single factor or circumstance that you can easily control and vary. Figure out what materials you will need. Make a list of the materials you actually use in your notebook!

Figure out what equipment you will need to take measurements and record data. Make a list of these in your lab notebook!

Set up several instances or trials of your observational situation, and vary your selected condition over a range of possible values, observe any changes in the behavior of the curious object and make your planned measurements. Be sure to have a control trial — one in which your variable factor isn't really a factor. This will help you identify whether other conditions may be affecting your outcome! Record your data in a useful format (perhaps a table organized by trial runs) in your lab notebook.

If your measurements require you to do so, make any necessary calculations. If you do your calculations using a spreadsheet or calculator, you should still include an example of your calculations in your lab notebook, and list your calculated data in your final report.

Now think about your data. Go back to your original observations and reflections and remind yourself what you were trying to discover about the curious object. Did your experiment cover the question you wanted to ask? Did it really test your hypothesis? What was the result (your hypothesis is true/false or needs refinement)? Put your thoughts and reflections in your notebook!

    You are ready to write your formal report. It should, of course, have a title, and each section should be clearly marked.
  1. Start by briefly describing the general observation that led you to investigate this particular phenomenon.
  2. State the hypothesis you wish to test, or the goal of your observation if you are not testing a true-false hypothesis (e.g., to determine what effect diameter has on the rate at which a candle burns).
  3. Identify your materials and equipment.
  4. Explain how you built any equipment or modified existing equipment for your experiment.
  5. Describe your procedure and your trial setup; be sure to include your control setup.
  6. List your data in a convenient format, one that allows the reader to see trends or discontinuities. Tables and graphs are good ways to show data.
  7. Show an example of your calculations (if any), and the final results of calculations for each of your trial runs.
  8. Summarize your conclusions. It's a good idea to also note what difficulties you ran into, any problems that might limit the applicability of your results to a general case, how these could be addressed in further experiments, and what the next steps in investigating your curious object should be.
  9. Write a short one-paragraph summary of your experiment and your conclusions as an abstract. This will actually go at the beginning of your report, but you can't really write it until the rest of the report exists.

There are a number of good sites on the web with details on lab report formats and how to write them. You may wish to consult